Semiconductor device structures including staircase structures, and related methods

ABSTRACT

A semiconductor device structure comprises stacked tiers each comprising at least one conductive structure and at least one insulating structure longitudinally adjacent the at least one conductive structure, at least one staircase structure having steps comprising lateral ends of the stacked tiers, and at least one opening extending through the stacked tiers and continuously across an entire length of the at least one staircase structure. The at least one conductive structure of each of the stacked tiers extends continuously from at least one of the steps of the at least one staircase structure and around the at least one opening to form at least one continuous conductive path extending completely across each of the stacked tiers. Additional semiconductor device structures, methods of forming semiconductor device structures, and electronic systems are also described.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.15/058,921, filed Mar. 2, 2016, pending, the disclosure of which ishereby incorporated herein in its entirety by this reference.

TECHNICAL FIELD

The disclosure, in various embodiments, relates generally to the fieldof semiconductor device design and fabrication. More specifically, thedisclosure relates to semiconductor device structures includingstaircase structures, and to related methods and electronic systems.

BACKGROUND

A continuing goal of the semiconductor industry has been to increase thememory density (e.g., the number of memory cells per memory die) ofmemory devices, such as non-volatile memory devices (e.g., NAND Flashmemory devices). One way of increasing memory density in non-volatilememory devices is to utilize vertical memory array (also referred to asa “three-dimensional (3D) memory array”) architectures. A conventionalvertical memory array includes semiconductor pillars extending throughopenings in tiers of conductive structures (e.g., word line plates,control gate plates) and dielectric materials at each junction of thesemiconductor pillars and the conductive structures. Such aconfiguration permits a greater number of switching devices (e.g.,transistors) to be located in a unit of die area by building the arrayupwards (e.g., longitudinally, vertically) on a die, as compared tostructures with conventional planar (e.g., two-dimensional) arrangementsof transistors.

Conventional vertical memory arrays include electrical connectionsbetween the conductive structures and access lines (e.g., word lines) sothat memory cells in the vertical memory array can be uniquely selectedfor writing, reading, or erasing operations. One method of forming suchan electrical connection includes forming a so-called “staircase” or“stair step” structure at edges of the tiers of conductive structures.The staircase structure includes individual “steps” defining contactregions of the conductive structures upon which contact structures canbe positioned to provide electrical access to the conductive structures.Unfortunately, conventional staircase structure fabrication techniquescan segment one or more conductive structures of a given tier, resultingin discontinuous conductive paths through the tier that can require theuse of multiple (e.g., more than one) switching devices to drivevoltages completely across the tier and/or in opposing directions acrossthe tier.

There remains a need for new semiconductor device structures, such asmemory array blocks for 3D non-volatile memory devices (e.g., 3D NANDFlash memory devices), as well as for associated memory devices andelectronic systems including the semiconductor device structures, andsimple, cost-efficient methods of forming semiconductor devicestructures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A through 1G are perspective (FIGS. 1A through 1F) and top-down(FIG. 1G) views illustrating a method of forming a semiconductor devicestructure, in accordance with embodiments of the disclosure.

FIG. 2 is a perspective view of a semiconductor device structure, inaccordance with additional embodiments of the disclosure.

FIGS. 3A through 3F are perspective (FIGS. 3A through 3E) and top-down(FIG. 3F) views illustrating a method of forming a semiconductor devicestructure, in accordance with further embodiments of the disclosure.

FIG. 4 is a perspective view of a semiconductor device structure, inaccordance with additional embodiments of the disclosure.

FIG. 5 is a perspective view of a semiconductor device structure, inaccordance with further embodiments of the disclosure.

FIG. 6 is a schematic block diagram illustrating an electronic system inaccordance with embodiments of the disclosure.

DETAILED DESCRIPTION

Semiconductor device structures (e.g., memory array blocks) includingstaircase structures are described, as are related methods andelectronic systems. In some embodiments, a semiconductor devicestructure includes stacked tiers each including at least one conductivestructure and at least one insulating structure longitudinally adjacentthe at least one conductive structure, one or more staircase structuresincluding steps defined by lateral ends of the stacked tiers, and one ormore openings extending through the stacked tiers and continuouslyacross an entire length of the at least one staircase structure. Theconductive structure of each of the stacked tiers may extendcontinuously from at least one of the steps of the at least onestaircase structure and around the opening (e.g., around ends and one ormore sides of the opening) to form a continuous conductive pathextending completely across each of the stacked tiers. In additionalembodiments, a semiconductor device structure formed in accordance withthe methods of the disclosure includes stacked tiers each includingconductive structures and insulating structures longitudinally adjacentthe conductive structures, stadium structures each including opposingstaircase structures having steps defined by lateral ends of the stackedtiers, at least one opening laterally intervening between at least twoof the stadium structures and extending through the stacked tiers andcontinuously across entire lengths of the at least two stadiumstructures, conductive contact structures coupled to the conductivestructures of the stacked tiers at steps of the opposing staircasestructures of at least one of the stadium structures, and conductiverouting structures coupled to and extending completely between pairs ofthe conductive contact structures to form at least one continuousconductive path extending completely across each of the stacked tiers.The structures and methods of the disclosure may permit individual(e.g., single) switching devices (e.g., transistors) of at least onestring driver device electrically connected to one or more conductivestructures of an individual tier to drive voltages completely acrossand/or in opposing directions across the tier. The structures andmethods of the disclosure may decrease the number of switching devicesand interconnections required to effectively operate a memory device,and may increase one or more of memory device performance, scalability,efficiency, and simplicity as compared to many conventional structuresand methods.

The following description provides specific details, such as materialcompositions and processing conditions, in order to provide a thoroughdescription of embodiments of the present disclosure. However, a personof ordinary skill in the art would understand that the embodiments ofthe present disclosure may be practiced without employing these specificdetails. Indeed, the embodiments of the present disclosure may bepracticed in conjunction with conventional semiconductor fabricationtechniques employed in the industry. In addition, the descriptionprovided below does not form a complete process flow for manufacturing asemiconductor device (e.g., a memory device). The semiconductor devicestructures described below do not form a complete semiconductor device.Only those process acts and structures necessary to understand theembodiments of the present disclosure are described in detail below.Additional acts to form a complete semiconductor device from thesemiconductor device structures may be performed by conventionalfabrication techniques.

Drawings presented herein are for illustrative purposes only, and arenot meant to be actual views of any particular material, component,structure, device, or system. Variations from the shapes depicted in thedrawings as a result, for example, of manufacturing techniques and/ortolerances, are to be expected. Thus, embodiments described herein arenot to be construed as being limited to the particular shapes or regionsas illustrated, but include deviations in shapes that result, forexample, from manufacturing. For example, a region illustrated ordescribed as box-shaped may have rough and/or nonlinear features, and aregion illustrated or described as round may include some rough and/orlinear features. Moreover, sharp angles that are illustrated may berounded, and vice versa. Thus, the regions illustrated in the figuresare schematic in nature, and their shapes are not intended to illustratethe precise shape of a region and do not limit the scope of the presentclaims. The drawings are not necessarily to scale. Additionally,elements common between figures may retain the same numericaldesignation.

As used herein, the terms “vertical”, “longitudinal”, “horizontal”, and“lateral” are in reference to a major plane of a structure and are notnecessarily defined by earth's gravitational field. A “horizontal” or“lateral” direction is a direction that is substantially parallel to themajor plane of the structure, while a “vertical” or “longitudinal”direction is a direction that is substantially perpendicular to themajor plane of the structure. The major plane of the structure isdefined by a surface of the structure having a relatively large areacompared to other surfaces of the structure.

As used herein, spatially relative terms, such as “beneath,” “below,”“lower,” “bottom,” “above,” “upper,” “top,” “front,” “rear,” “left,”“right,” and the like, may be used for ease of description to describeone element's or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. Unless otherwise specified,the spatially relative terms are intended to encompass differentorientations of the materials in addition to the orientation depicted inthe figures. For example, if materials in the figures are inverted,elements described as “below” or “beneath” or “under” or “on bottom of”other elements or features would then be oriented “above” or “on top of”the other elements or features. Thus, the term “below” can encompassboth an orientation of above and below, depending on the context inwhich the term is used, which will be evident to one of ordinary skillin the art. The materials may be otherwise oriented (e.g., rotated 90degrees, inverted, flipped) and the spatially relative descriptors usedherein interpreted accordingly.

As used herein, the singular forms “a,” “an,” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

As used herein, “and/or” includes any and all combinations of one ormore of the associated listed items.

As used herein, the term “configured” refers to a size, shape, materialcomposition, and arrangement of one or more of at least one structureand at least one apparatus facilitating operation of one or more of thestructure and the apparatus in a pre-determined way.

As used herein, the phrase “coupled to” refers to structures operativelyconnected with each other, such as electrically connected through adirect ohmic connection or through an indirect connection (e.g., viaanother structure).

As used herein, the term “mirrors” means and includes that at least twostructures are mirror images of one another. As a non-limiting example,a first staircase structure that mirrors a second staircase structuremay exhibit the substantially the same size and substantially the sameshape as the second staircase structure, but may outwardly extend in adirection that opposes a direction in which the second structureoutwardly extends. The first staircase structure may, for example,exhibit a generally negative slope, and the second staircase structuremay exhibit a generally positive slope.

As used herein, the term “substantially” in reference to a givenparameter, property, or condition means and includes to a degree thatone of ordinary skill in the art would understand that the givenparameter, property, or condition is met with a degree of variance, suchas within acceptable manufacturing tolerances. By way of example,depending on the particular parameter, property, or condition that issubstantially met, the parameter, property, or condition may be at least90.0% met, at least 95.0% met, at least 99.0% met, or even at least99.9% met.

As used herein, the term “about” in reference to a given parameter isinclusive of the stated value and has the meaning dictated by thecontext (e.g., it includes the degree of error associated withmeasurement of the given parameter).

FIGS. 1A through 1G are simplified perspective (FIGS. 1A through 1F) andtop-down (FIG. 1G) views illustrating embodiments of a method of forminga semiconductor device structure including a staircase structure, suchas a memory array structure (e.g., a memory array block) for a 3Dnon-volatile memory device (e.g., a 3D NAND Flash memory device). Withthe description provided below, it will be readily apparent to one ofordinary skill in the art that the methods described herein may be usedin various devices. In other words, the methods of the disclosure may beused whenever it is desired to form a semiconductor device including astaircase structure.

Referring to FIG. 1A, a semiconductor device structure 100 may include astack structure 102 exhibiting an alternating sequence of insulatingstructures 104 and additional insulating structures 106 arranged intiers 108. Each of the tiers 108 may include one of the insulatingstructures 104 and one of the additional insulating structures 106. Forclarity and ease of understanding of the drawings and relateddescription, FIG. 1A shows the stack structure 102 as including eleven(11) tiers 108 (i.e., tiers 108 a through 108 k) of the insulatingstructures 104 and the additional insulating structures 106. However,the stack structure 102 may include a different number of tiers 108. Forexample, in additional embodiments, the stack structure 102 may includegreater than eleven (11) tiers 108 (e.g., greater than or equal tofifteen (15) tiers 108, greater than or equal to twenty-five (25) tiers108, greater than or equal to fifty (50) tiers 108, greater than orequal to one hundred (100) tiers 108) of the insulating structures 104and the additional insulating structures 106, or may include less thaneleven (11) tiers 108 (e.g., less than or equal to ten (10) tiers 108,less than or equal to five (5) tiers 108, less than or equal to three(3) tiers 108) of the insulating structures 104 and the additionalinsulating structures 106.

The insulating structures 104 may be formed of and include at least oneinsulating material, such as one or more of an oxide material (e.g.,silicon dioxide, phosphosilicate glass, borosilicate glass,borophosphosilicate glass, fluorosilicate glass, titanium dioxide,zirconium dioxide, hafnium dioxide, tantalum oxide, magnesium oxide,aluminum oxide, or a combination thereof), a nitride material (e.g.,silicon nitride), an oxynitride material (e.g., silicon oxynitride), andamphorous carbon. Each of the insulating structures 104 mayindependently include a substantially homogeneous distribution or asubstantially heterogeneous distribution of the at least one insulatingmaterial. In some embodiments, each of the insulating structures 104exhibits a substantially homogeneous distribution of insulatingmaterial. In additional embodiments, at least one of the insulatingstructures 104 exhibits a substantially heterogeneous distribution of atleast one conductive material. One or more of the insulating structures104 may, for example, be formed of and include a stack (e.g., laminate)of at least two different insulating materials. In some embodiments,each of the insulating structures 104 is formed of and includes silicondioxide. The insulating structures 104 may each be substantially planar,and may each independently exhibit any desired thickness. In addition,each of the insulating structures 104 may be substantially the same(e.g., exhibit substantially the same material composition, materialdistribution, size, and shape) as one another, or at least one of theinsulating structures 104 may be different (e.g., exhibit one or more ofa different material composition, a different material distribution, adifferent size, and a different shape) than at least one other of theinsulating structures 104. In some embodiments, each of the insulatingstructures 104 is substantially the same as each other of the insulatingstructures 104.

The additional insulating structures 106 may each be formed of andinclude at least one additional insulating material that may beselectively removable relative to the insulating material of theinsulating structures 104. The at least one additional insulatingmaterial of the additional insulating structures 106 may be differentthan the insulating material of the insulating structures 104, and maycomprise one or more of an oxide material (e.g., silicon dioxide,phosphosilicate glass, borosilicate glass, borophosphosilicate glass,fluorosilicate glass, titanium dioxide, zirconium dioxide, hafniumdioxide, tantalum oxide, magnesium oxide, aluminum oxide, orcombinations thereof), a nitride material (e.g., silicon nitride), anoxynitride material (e.g., silicon oxynitride), and amphorous carbon.Each of the additional insulating structures 106 may independentlyinclude a substantially homogeneous distribution or a substantiallyheterogeneous distribution of the at least one additional insulatingmaterial. In some embodiments, each of the additional insulatingstructures 106 exhibits a substantially homogeneous distribution ofadditional insulating material. In further embodiments, at least one ofthe additional insulating structures 106 exhibits a substantiallyheterogeneous distribution of at least one conductive material. One ormore of the additional insulating structures 106 may, for example, beformed of and include a stack (e.g., laminate) of at least two differentadditional insulating materials. In some embodiments, each of theadditional insulating structures 106 is formed of and includes siliconnitride. The additional insulating structures 106 may each besubstantially planar, and may each independently exhibit any desiredthickness. In addition, each of the additional insulating structures 106may be substantially the same (e.g., exhibit substantially the samematerial composition, material distribution, size, and shape) as oneanother, or at least one of the additional insulating structures 106 maybe different (e.g., exhibit one or more of a different materialcomposition, a different material distribution, a different size, and adifferent shape) than at least one other of the additional insulatingstructures 106. In some embodiments, each of the additional insulatingstructures 106 is substantially the same as each other of the additionalinsulating structures 106. The additional insulating structures 106 mayserve as sacrificial structures for the subsequent formation ofconductive structures, as described in further detail below.

As shown in FIG. 1A, in some embodiments, the alternating sequence ofthe insulating structures 104 and the additional insulating structures106 begins with one of the insulating structures 104. In additionalembodiments, the insulating structures 104 and the additional insulatingstructures 106 exhibit a different arrangement relative to one another.By way of non-limiting example, the insulating structures 104 and theadditional insulating structures 106 may be arranged in an alternatingsequence beginning with one of the additional insulating structures 106.In some embodiments, each of the tiers 108 includes one of theadditional insulating structures 106 on or over one of the insulatingstructures 104. In additional embodiments, each of the tiers 108includes one of the insulating structures 104 on or over one of theadditional insulating structures 106.

The stack structure 102, including the each of the tiers 108 thereof,may be formed using conventional processes (e.g., conventionaldeposition processes, conventional material removal processes) andconventional processing equipment, which are not described in detailherein. By way of non-limiting example, the insulating structures 104and the additional insulating structures 106 may be formed through oneor more of in situ growth, spin-on coating, blanket coating, chemicalvapor deposition (CVD), plasma enhanced chemical vapor deposition(PECVD), atomic layer deposition (ALD), and physical vapor deposition(PVD).

Referring next to FIG. 1B, a masking structure 110 may be formed on orover the stack structure 102. The masking structure 110 may be formed ofand include at least one material (e.g., at least one hard maskmaterial) suitable for use as an etch mask to pattern portions of thestack structure 102 (e.g., portions of the tiers 108, including portionsof the insulating structures 104 and portions of the additionalinsulating structures 106, remaining uncovered by the masking structure110) to form at least one staircase structure, as described in furtherdetail below. By way of non-limiting example, the masking structure 110may be formed of and include at least one of amorphous carbon, silicon,a silicon oxide, a silicon nitride, a silicon oxycarbide, aluminumoxide, and a silicon oxynitride. The masking structure 110 may behomogeneous (e.g., may comprise a single material layer), or may beheterogeneous (e.g., may comprise a stack exhibiting at least twodifferent material layers).

The position and dimensions of the masking structure 110 may be selectedat least partially based on desired positions and desired dimensions ofone or more staircase structures to be subsequently formed in the stackstructure 102. By way of non-limiting example, as shown in FIG. 1B, themasking structure 110 may be centrally positioned on or over the stackstructure 102 in the Y-direction, may have a width W₂ less than thewidth W₁ of the stack structure 102, and may have substantially the samelength L₁ as the stack structure 102. Widths of portions of the stackstructure 102 remaining uncovered by (e.g., not underlying) the maskingstructure 110 may correspond to widths of the one or more staircasestructures to be subsequently formed in the stack structure 102. Inadditional embodiments, the masking structure 110 may exhibit one ormore of a different position (e.g., a different position in one or moreof the X-direction and the Y-direction), a different width W₂, and adifferent length (e.g., a length less than the length L₁). As anon-limiting example, the masking structure 110 may be centrallypositioned on or over the stack structure 102 in each of the Y-directionand the X-direction, may have a width W₂ less than the width W₁ of thestack structure 102, and may have a length less than the length L₁ ofthe stack structure 102. As another non-limiting example, the maskingstructure 110 may be non-centrally positioned over the stack structure102 in the Y-direction, may have a width W₂ less than the width W₁ ofthe stack structure 102, and may have substantially the same length L₁as the stack structure 102. The masking structure 110 may be formed onor over the stack structure 102 to any desired thickness.

The masking structure 110 may be formed using conventional processes(e.g., conventional deposition processes, such as at least one of insitu growth, spin-on coating, blanket coating, CVD, PECVD, ALD, and PVD,conventional photolithography processes, conventional material removalprocesses) and conventional processing equipment, which are notdescribed in detail herein.

Referring to next to FIG. 1C, portions of the stack structure 102 (FIG.1B) (e.g., portions of one or more of the tiers 108) remaining uncoveredby the masking structure 110 may be subjected to at least one materialremoval process (e.g., one or more of a trimming process and a choppingprocess) to form a modified stack structure 112. The modified stackstructure 112 may include one or more staircase structures 114 eachindependently formed of and including one or more steps 116. The steps116 of the one or more staircase structures 114 may be at leastpartially defined by exposed portions of one or more of the tiers 108remaining following the at least one material removal process.

The modified stack structure 112 may include a single (e.g., only one)staircase structure 114, or may include multiple (e.g., more than one)staircase structures 114. In some embodiments, the modified stackstructure 112 includes multiple staircase structures 114. By way ofnon-limiting example, as shown in FIG. 1C, the modified stack structure112 may include one or more so-called stadium structures 118 eachincluding opposing staircase structures 114. A first stadium structure118 a may be positioned along one side of the masking structure 110, anda second stadium structure 118 b may be positioned along an opposingside of the masking structure 110. The first stadium structure 118 a mayinclude a first forward staircase structure 114 a, and a first reversestaircase structure 114 b that mirrors the first forward staircasestructure 114 a. The second stadium structure 118 b may extend parallelto the first stadium structure 118 a (e.g., the first stadium structure118 a and the second stadium structure 118 b may both extend in theX-direction), and may include a second forward staircase structure 114c, and a second reverse staircase structure 114 d that mirrors thesecond forward staircase structure 114 c. The first stadium structure118 a and the second stadium structure 118 b may be substantiallysimilar to one another (e.g., may exhibit substantially the same shapesand sizes as one another), or may be different than one another (e.g.,may exhibit one or more of different shapes and different sizes than oneanother). In some embodiments, the first stadium structure 118 a and thesecond stadium structure 118 b are substantially similar to one another.The first stadium structure 118 a and the second stadium structure 118 bmay serve as redundant and/or alternative means of connecting to one ormore of the tiers 108 of the modified stack structure 112, as may theopposing staircase structures (e.g., the first forward staircasestructure 114 a and the first reverse staircase structure 114 b of thefirst stadium structure 118 a, and/or the second forward staircasestructure 114 c and the second reverse staircase structure 114 d of thesecond stadium structure 118 b) of one or more of the first stadiumstructure 118 a and the second stadium structure 118 b.

In additional embodiments, the modified stack structure 112 may exhibitone or more of a different number and different configuration of thestaircase structures 114. By way of non-limiting example, the modifiedstack structure 112 may include only one (1) stadium structure 118(e.g., only the first stadium structure 118 a, or only the secondstadium structure 118 b), may include more than two (2) stadiumstructures 118 extending parallel to one another, may include two ormore stadium structures 118 extending in series with one another, mayinclude one or more forward staircase structures (e.g., one or more ofthe first forward staircase structure 114 a and the second forwardstaircase structure 114 c) but not one or more reverse staircasestructures (e.g., one or more of the first reverse staircase structure114 b and the second reverse staircase structure 114 d may be omitted),may include one or more reverse staircase structures (e.g., one or moreof the first reverse staircase structure 114 b and the second reversestaircase structure 114 d) but not one or more forward staircasestructures (e.g., one or more of the first forward staircase structure114 a and the second forward staircase structure 114 c may be omitted),may include two or more forward staircase structures extending in serieswith one another, and/or may include two or more reverse staircasestructures extending in series with one another.

Each of the staircase structures 114 included in the modified stackstructure 112 may independently include a desired number of steps 116.The number of steps 116 included in each of the staircase structures 114may be substantially the same as (e.g., equal to) or may be differentthan (e.g., less than, or greater than) the number of tiers 108 in themodified stack structure 112. In some embodiments, the number of steps116 included in each of the staircase structures 114 is less than thenumber of tiers 108 in the modified stack structure 112. As anon-limiting example, as shown in FIG. 1C, each of the staircasestructures 114 (e.g., the first forward staircase structure 114 a, thefirst reverse staircase structure 114 b, the second forward staircasestructure 114 c, and the second reverse staircase structure 114 d) mayinclude ten (10) steps 116 at least partially defined by ends of theeleven (11) tiers 108 (e.g., tiers 108 a through 108 k) of the modifiedstack structure 112. In additional embodiments, one or more of thestaircase structures 114 may include a different number of steps 116(e.g., less than ten (10) steps 116, greater than ten (10) steps 116).By way of non-limiting example, if the modified stack structure 112includes eleven (11) tiers 108, at least one of the staircase structures114 may include five (5) steps 116 at least partially defined by ends ofa relatively lower group of the tiers 108 (e.g., tier 108 f through tier108 k), and at least one other of the staircase structures 114 mayinclude five (5) steps 116 at least partially defined by ends of arelatively higher group of the tiers 108 (e.g., tiers 108 a through 108e).

The dimensions of each of the steps 116 may independently be tailored todesired dimensions and positions of additional structures (e.g.,conductive structures, conductive contact structures) and/or openings(e.g., slots) to be formed in, on, over, and/or adjacent to the steps116 during subsequent processing of the semiconductor device structure100, as described in further detail below. In some embodiments, each ofthe steps 116 exhibits substantially the same dimensions (e.g.,substantially the same width, substantially the same length, andsubstantially the same height) as each other of the steps 116. Inadditional embodiments, at least one of the steps 116 exhibits differentdimensions (e.g., one or more of a different width, a different length,and a different height) than at least one other of the steps 116.

The staircase structures 114 may be formed using conventional processes(e.g., conventional photolithography processes, conventional materialremoval processes) and conventional processing equipment, which are notdescribed in detail herein. By way of non-limiting example, aphotoresist structure may be formed on or over at least uncoveredportions of the stack structure 102 (FIG. 1B), the photoresist structuremay be photolithographically processed (e.g., photoexposed anddeveloped) to remove at least one width thereof, one or more of thetiers 108 may be etched (e.g., anisotropically etched, such asanisotropically dry etched) using the masking structure 110 andremaining portions of the photoresist structure as etching masks, thephotoresist structure may be subjected to additional photolithographicprocessing to remove at least one additional width thereof, at leastanother group of the tiers 108 (e.g., previously etched tiers 108 andone or more additional tiers 108) may be etched using the maskingstructure 110 and newly remaining portions of the photoresist structureas etching masks, and so on, until the modified stack structure 112including the one or more staircase structures 114 is formed.

Referring next to FIG. 1D, the masking structure 110 (FIG. 1C) may beremoved, and one or more openings 120 (e.g., slots, apertures, slits)may be formed in the modified stack structure 112. The masking structure110 may be removed using one or more conventional material removalprocesses, which are not described in detail herein. By way ofnon-limiting example, the masking structure 110 may be selectivelyremoved through at least one conventional etching process (e.g., aconventional wet etching process, a conventional dry etching process).

The openings 120 may longitudinally extend (e.g., in the Z-direction)through (e.g., completely through) the modified stack structure 112, maybe positioned laterally inward (e.g., in the Y-direction) of thestaircase structures 114, and may continuously laterally extend (e.g.,in the X-direction) across the entire lengths of the staircasestructures 114. By way of non-limiting example, as shown in FIG. 1D, theopenings 120 may extend completely through each of the tiers 108, may bepositioned laterally inwardly adjacent the stadium structures 118, andmay continuously laterally extend across the entire lengths of thestadium structures 118. A first opening 120 a may be positionedlaterally between (e.g., in the Y-direction) the first stadium structure118 a and a remaining middle section 122 of the modified stack structure112, and may laterally extend (e.g., in the X-direction) from a top(e.g., a laterally inward end of tier 108 a) of the first forwardstaircase structure 114 a to a top (e.g., an opposing laterally inwardend of tier 108 a) of the first reverse staircase structure 114 b. Asecond opening 120 b may be positioned laterally between (e.g., in theY-direction) the second stadium structure 118 b and the remaining middlesection 122 of the modified stack structure 112, and may laterallyextend parallel (e.g., in the X-direction) to the first opening 120 afrom a top (e.g., a laterally inward end of tier 108 a) of the secondforward staircase structure 114 c to a top (e.g., an opposing laterallyinward end of tier 108 a) of the second reverse staircase structure 114d.

In additional embodiments, one or more of the openings 120 may exhibit adifferent configuration than that depicted in FIG. 1D. As a non-limitingexample, in embodiments wherein the modified stack structure 112includes at least one forward staircase structure (e.g., the firstforward staircase structure 114 a, and/or the second forward staircasestructure 114 c) but not at least one reverse staircase structure (e.g.,not at least one of the first reverse staircase structure 114 b and thesecond reverse staircase structure 114 d) opposing the forward staircasestructure, the opening 120 may be positioned laterally inward (e.g.,laterally adjacent) the forward staircase structure and maylongitudinally extend completely through the tiers 108, but maycontinuously laterally extend from a top (e.g., a laterally inward endof the tier 108 a) of the forward staircase structure to a bottom (e.g.,as defined by one or more of the tier 108 k and the tier 108 j) of theforward staircase structure. As another non-limiting example, inembodiments wherein the modified stack structure 112 includes at leastone reverse staircase structure (e.g., the first reverse staircasestructure 114 b, and/or the second reverse staircase structure 114 d)but not at least one forward staircase structure (e.g., not at least oneof the first forward staircase structure 114 a and the second forwardstaircase structure 114 c) opposing the reverse staircase structure, theopening 120 may be positioned laterally inward (e.g., laterallyadjacent) the reverse staircase structure and may longitudinally extendcompletely through the tiers 108, but may continuously laterally extendfrom a bottom (e.g., as defined by one or more of the tier 108 k and thetier 108 j and) of the reverse staircase structure to a top (e.g., alaterally inward end of the tier 108 a) of the reverse staircasestructure.

Any desired number (e.g., quantity, amount) of openings 120 may beformed in the modified stack structure 112. The number of openings 120may correspond to desired configurations (e.g., shapes, sizes,positions) of conductive structures to be formed in the modified stackstructure 112 through subsequent processing acts, as described infurther detail below. A single (e.g., only one) opening 120 may beformed laterally inward (e.g., in the Y-direction) of the staircasestructures 114 and may continuously laterally extend across and between(e.g., in the X-direction) the staircase structures 114, or multiple(e.g., more than one) openings 120 may be formed laterally inward (e.g.,in the Y-direction) of the staircase structures 114 and may continuouslylaterally extend in parallel across and between (e.g., in theX-direction) the staircase structures 114. As shown in FIG. 1D, in someembodiments, two (2) openings 120 (e.g., the first opening 120 a, andthe second opening 120 b) are formed in the modified stack structure112. The two (2) openings 120 may be disposed between the stadiumstructures 118 (e.g., the first stadium structure 118 a, and the secondstadium structure 118 b) of the modified stack structure 112, and mayflank opposing sides of the remaining middle section 122 of the modifiedstack structure 112. In additional embodiments, more than two (2)openings 120 are formed in the modified stack structure 112. Forexample, at least one additional opening (e.g., a third opening) may beformed in the remaining middle section 122 of the modified stackstructure 112 (e.g., laterally between the first opening 120 a and thesecond opening 120 b). The at least one additional opening may extendcompletely longitudinally through the remaining middle section 122 ofthe modified stack structure 112, and may continuously laterally extendacross the remaining middle section 122 in parallel to the otheropenings 120 (e.g., the first opening 120 a, and the second opening 120b).

The dimensions and spacing of the one or more openings 120 may beselected to provide desired dimensions (e.g., widths) to and/or maintaindesired dimensions of the staircase structures 114 (including the steps116 thereof), and to provide desired dimensions (e.g., widths),continuity, and spacing to conductive structures to be formed using theopenings 120, as described in further detail below. If more than oneopening 120 is formed in the modified stack structure 112, each of theopenings 120 may exhibit substantially the same dimensions (e.g.,substantially the same width, substantially the same length, andsubstantially the same height), or at least one of the openings 120 mayexhibit one or more different dimensions (e.g., a different width, adifferent length, and/or a different height) than at least one other ofthe openings 120. In some embodiments, each of the openings 120 exhibitssubstantially the same dimensions. In addition, if more than two (2)openings 120 are formed in the modified stack structure 112, adjacentopenings 120 may be substantially uniformly (e.g., evenly) spaced apartfrom one another, or may be non-uniformly (non-evenly) spaced apart fromone another. In some embodiments, adjacent openings 120 aresubstantially uniformly spaced apart from one another. The openings 120may be symmetrically distributed across the modified stack structure112, or may be asymmetrically distributed across the modified stackstructure 112.

The openings 120 may be formed in the modified stack structure 112 usingat least one conventional material removal processes, which is notdescribed in detail herein. For example, one or more portions of themodified stack structure 112 may be subjected to at least one etchingprocess (e.g., at least one dry etching process, such as at least one ofa reactive ion etching (RIE) process, a deep RIE process, a plasmaetching process, a reactive ion beam etching process, and a chemicallyassisted ion beam etching process; at least one wet etching process,such as at least one of a hydrofluoric acid etching process, a bufferedhydrofluoric acid etching process, and a buffered oxide etching process)to form the openings 120 in the modified stack structure 112. Thematerial removal process may remove one or more portions of thestaircase structures 114 (e.g., so as to reduce widths of the staircasestructures 114), and/or may remove one or more portions of the modifiedstack structure 112 previously covered by the masking structure 110(FIG. 1C).

Referring next to FIG. 1E, portions of the additional insulatingstructures 106 (FIG. 1D) may be selectively removed, and may be replacedwith a conductive material to form a conductive stack structure 124. Asshown in FIG. 1E, each of the tiers 108 of the conductive stackstructure 124 may include one or more conductive structures 126 (e.g.,conductive gates, conductive plates) extending (e.g., in the X-directionand/or in the Y-direction) into lateral surfaces thereof. The one ormore conductive structures 126 of each tier 108 of the conductive stackstructure 126 may at least partially (e.g., substantially) laterallysurround remaining portions 128 (e.g., unremoved portions) of theadditional insulating structures 106.

The conductive structures 126 may follow (e.g., route along) lateral(e.g., side) surfaces of the conductive stack structure 124. Forexample, the conductive structures 126 may extend into and along outerlateral surfaces (e.g., peripheral lateral surfaces) of the tiers 108,as well as into and along inner lateral surfaces of the tiers 108 (e.g.,lateral surfaces at least partially defined by the openings 120longitudinally extending through the tiers 108). For each of the tiers108, the conductive structures 126 may laterally extend to and aroundeach of the openings 120 (e.g., completely around ends of the openings120, and completely across the portions of the middle section 122 of theconductive stack structure 124 adjacent the openings 120) to form one ormore continuous conductive paths between a first end 130 of theconductive stack structure 124 and a second, opposing end 132 of theconductive stack structure 124. The first end 130 and the second,opposing end 132 of the conductive stack structure 124 may each becoupled to other components of a semiconductor device (e.g., a memorydevice) including the semiconductor device structure 100, such as one ormore memory cell arrays (e.g., vertical memory cell arrays). Inaddition, portions of at least some of the conductive structures 126 maylaterally extend (e.g., in the X-direction) to and at least partiallydefine the staircase structures 114 of the conductive stack structure124 to form conductive contact regions (e.g., landing pad regions) forat least some of the tiers 108. For each of the conductive structures126, portions thereof laterally extending to and at least partiallydefining one or more of the staircase structures 114 may be integral andcontinuous with other portions thereof laterally extending to and aroundthe openings 120 positioned laterally inward of (e.g., laterallyinwardly adjacent) the staircase structures 114. Furthermore, in tiers108 longitudinally below the staircase structures 114 (e.g., untrimmedtiers 108 and/or unchopped tiers 108), the conductive structures 126thereof may laterally extend to and may completely surround the openings120.

In some embodiments, the conductive stack structure 124 includesmultiple (e.g., more than one) conductive structures 126 in one or more(e.g., each) of the tiers 108 thereof. By way of non-limiting example,as shown in FIG. 1E, each of the one or more tiers 108 may include oneconductive structure 126 at least partially defining the first stadiumstructure 118 a and surrounding sides of the first opening 120 a, andmay also include an additional conductive structure 126 at leastpartially defining the second stadium structure 118 b and surroundingsides of the second opening 120 b. The conductive structures 126associated with the first stadium structure 118 a and the first opening120 a may each extend laterally inward from the first end 130 and thesecond, opposing end 132 of the conductive stack structure 124 alongouter lateral surfaces of the conductive stack structure 124 to thefirst stadium structure 118 a, wherein portions of each of theconductive structures 126 may at least partially define the firststadium structure 118 a (e.g., including the first forward staircasestructure 114 a and the first reverse staircase structure 114 b) andother portions of each of the conductive structures 126 may extendaround inner lateral surfaces of the conductive stack structure 124 atleast partially defined by the first opening 120 a. The additionalconductive structures 126 associated with the second stadium structure118 b and the second opening 120 b may each extend laterally inward fromthe first end 130 and the second, opposing end 132 of the conductivestack structure 124 along other outer lateral surfaces of the conductivestack structure 124 to the second stadium structure 118 b, whereinportions of each of the additional conductive structures 126 may atleast partially define the second stadium structure 118 b (e.g.,including the second forward staircase structure 114 c and the secondreverse staircase structure 114 d) and other portions of each of theadditional conductive structures 126 may extend around inner lateralsurfaces of the conductive stack structure 124 at least partiallydefined by the second opening 120 b. For each of the tiers 108, themultiple conductive structures 126 may be separated (e.g., isolated)from one another by the remaining portion 128 of the additionalinsulating structure 106 (FIG. 1D). For example, as shown in FIG. 1E,for each of the different tiers 108 (e.g., each of the tiers 108 athrough 108 k) of the conductive stack structure 124, a conductivestructure 126 associated with the first stadium structure 118 a and thefirst opening 120 a may be separated from an additional conductivestructure 126 associated with the second stadium structure 118 b and thesecond opening 120 b by the remaining portion 128 of the additionalinsulating structure 106.

In additional embodiments, the conductive stack structure 124 includes asingle (e.g., only one) conductive structure 126 in one or more (e.g.,each) of the tiers 108 thereof. The single conductive structure 126 ofeach of the one or more tiers 108 may at least partially define each ofthe staircase structures 114, and may surround sides of each of theopenings 120. For each of the one or more tiers 108, all portions of thesingle conductive structure 126 thereof may be integral and continuouswith one another, and may form a continuous conductive path extendingfrom the first end 130 of the conductive stack structure 124 to thesecond, opposing end 132 of the of the conductive stack structure 124.By way of non-limiting example, in embodiments wherein the conductivestack structure 124 includes at least one additional opening laterallybetween the first opening 120 a and the second opening 120 b, each ofthe tiers 108 may include a single conductive structure 126 at leastpartially defining each of the first stadium structure 118 a and thesecond stadium structure 118 b and surrounding sides of each of thefirst opening 120 a, the second opening 120 b, and the at least oneadditional opening. The single conductive structure 126 may extendlaterally inward from the first end 130 and the second, opposing end 132of the conductive stack structure 124 along outer lateral surfaces ofthe conductive stack structure 124 to each of the first stadiumstructure 118 a and the second stadium structure 118 b, wherein portionsof the single conductive structure 126 may extend into and at leastpartially define the first stadium structure 118 a (e.g., including thefirst forward staircase structure 114 a and the first reverse staircasestructure 114 b) and second stadium structure 118 b (e.g., including thesecond forward staircase structure 114 c and the second reversestaircase structure 114 d) and other portions of the single conductivestructure 126 may extend around inner lateral surfaces of the tier 108at least partially defined by one or more of the first opening 120 a,the second opening 120 b, and the additional opening. In suchembodiments, the remaining portions 128 of the additional insulatingstructure 106 (FIG. 1D) laterally intervening between the first opening120 a and the second opening 120 b may be absent (e.g., omitted) fromthe conductive stack structure 124.

The dimensions and shapes of the conductive structures 126 may directlycorrespond to the dimensions and shapes of the removed portions of theadditional insulating structures 106 (FIG. 1D). A width (e.g., lateraldepth within the conductive stack structure 124) of each of theconductive structures 126 may be substantially uniform across the entirepath (e.g., route) of the conductive structure 126, or the width of atleast one of the conductive structures 126 may be substantiallynon-uniform (e.g., variable) across different portions of the path ofthe conductive structure 126. In addition, each of the conductivestructures 126 may exhibit a different shape and at least one differentdimension than each other of the conductive structures 126, or at leastone of the conductive structures 126 may exhibit one or more ofsubstantially the same shape and substantially the same dimensions as atleast one other of the conductive structures 126. By way of non-limitingexample, as shown in FIG. 1E, conductive structures 126 of differenttiers 108 may exhibit different shapes and different dimensions (e.g.,different lengths associated with the locations of the different steps116 of the staircase structures 114) than one another, but conductivestructures 126 within the same tier 108 may exhibit substantially thesame shapes and substantially the same dimensions as one another (e.g.,conductive structures 126 within the same tier 108 may be mirror imagesof one another). In additional embodiments, conductive structures 126 oftwo or more different tiers 108 may exhibit substantially the sameshapes and substantially the same dimensions as one another. In furtherembodiments, conductive structures 126 within the same tier 108 mayexhibit one or more of a different shape and at least one differentdimension than one another.

The conductive structures 126 may be formed of and include at least oneconductive material, such as a metal, a metal alloy, a conductive metaloxide, a conductive metal nitride, a conductive metal silicide, aconductively-doped semiconductor material, or combinations thereof. Byway of non-limiting example, the conductive structures 126 may be formedof and include at least one of tungsten (W), tungsten nitride (WN),nickel (Ni), tantalum (Ta), tantalum nitride (TaN), tantalum silicide(TaSi), platinum (Pt), copper (Cu), silver (Ag), gold (Au), aluminum(Al), molybdenum (Mo), titanium (Ti), titanium nitride (TiN), titaniumsilicide (TiSi), titanium silicon nitride (TiSiN), titanium aluminumnitride (TiAlN), molybdenum nitride (MoN), iridium (Ir), iridium oxide(IrO_(x)), ruthenium (Ru), ruthenium oxide (RuO_(x)), andconductively-doped silicon. In some embodiments, the conductivestructures 126 are formed of and include W.

The conductive structures 126 may be formed by selectively removingportions of the additional insulating structures 106 (FIG. 1D) relativeto the insulating structures 104 to form recessed regions laterallyextending into each of the tiers 108, and then at least partially (e.g.,substantially) filling the recessed regions with at least one conductivematerial. The recessed regions may be formed by subjecting the modifiedstack structure 112 (FIG. 1D) to at least one etching processing (e.g.,an isotropic etching process) employing an etch chemistry in which theinsulative material of the additional insulating structures 106 (FIG.1D) is selectively removed relative to that of the insulating structures104. By way of non-limiting example, if the insulating structures 104are formed of and include silicon dioxide (SiO₂), and the additionalinsulating structures 106 are formed of and include silicon nitride(Si₃N₄), the modified stack structure 112 may be exposed to an etchantcomprising phosphoric acid (H₃O₄P) to selectively remove portions of theadditional insulating structures 106 adjacent exposed lateral surfaces(e.g., exposed outer lateral surfaces, exposed inner lateral surfaces atleast partially defined by the openings 120) of the modified stackstructure 112. Thereafter, the conductive material may be formed (e.g.,delivered, deposited) within recessed regions to form the conductivestructures 126.

In additional embodiments, rather than selectively removing andreplacing portions of the additional insulating structures 106 (FIG. 1D)to form the conductive stack structure 124, portions of the insulatingstructures 104 may instead be selectively removed and replaced withconductive material to form a conductive stack structure. Aside from thesequence (e.g., order) of the alternating conductive structures andinsulating structures of such a conductive stack structure anddifferences (if any) associated with material properties of theinsulating structures 104 as compared to those of the additionalinsulating structures 106, such a conductive stack structure may besubstantially similar to and may have little or no difference in termsof functionality and/or operability as compared to the conductive stackstructure 124 depicted in FIG. 1E.

Referring next to FIG. 1F, conductive contact structures 134 (e.g.,conductive plugs, conductive vertical interconnects) may be formed on,over, and/or within the one or more of staircase structures 114 of theconductive stack structure 124, and conductive routing structures 136(e.g., conductive interconnects, conductive bridges) may be formed toelectrically connect the conductive contact structures 134 to at leastone string driver device 138. FIG. 1G is a top-down view of thesemiconductor device structure 100 at the processing stage depicted inFIG. 1F.

The conductive contact structures 134 may be coupled to the conductivestructures 126 of the tiers 108 of the conductive stack structure 124 atthe steps 116 of the staircase structures 114. Each of the tiers 108(e.g., each of the tiers 108 a through 108 k) may have one or more ofthe conductive contact structures 134 coupled to the conductivestructure(s) 126 thereof, or less than all of the tiers 108 (e.g., lessthan all of the tiers 108 a through 108 k, such as only tiers 108 bthrough 108 j) may have one or more of the conductive contact structures134 coupled to the conductive structure(s) 126 thereof. Each of thetiers 108 including one or more of the conductive contact structures 134coupled to the conductive structure(s) 126 thereof may include a single(e.g., only one) conductive contact structure 134 coupled to theconductive structure(s) 126 thereof, or may include multiple (e.g., morethan one) conductive contact structures 134 coupled thereto. As anon-limiting example, as shown in FIG. 1F, in embodiments wherein eachof the tiers 108 includes multiple conductive structures 126 (e.g.,multiple conductive structures 126 laterally isolated from one anotherby the remaining portion 128 of one of the additional insulatingstructures 106 (FIG. 1D)), each conductive structure 126 of a given tier108 may have at least one of the conductive contact structures 134coupled thereto at one or more of the steps 116 (e.g., one or more ofthe steps 116 of the first stadium structure 118 a, one or more of thesteps 116 of the second stadium structure 118 b) at least partiallydefined by the conductive structure 126. As another non-limitingexample, in embodiments wherein each of the tiers 108 includes a single(e.g., only one) conductive structure 126, the single conductivestructure 126 may have at least one of the conductive contact structures134 coupled thereto at one or more of the steps 116 at least partiallydefined by the single conductive structure 126.

The conductive contact structures 134 may be formed on or over a single(e.g., only one) staircase structure 114 of the conductive stackstructure 124, or may be formed on or over multiple (e.g., more thanone) staircase structures 114 of the conductive stack structure 124. Byway of non-limiting example, as shown in FIGS. 1F and 1G, within atleast one of the stadium structures 118 (e.g., at least one of the firststadium structure 118 a and the second stadium structure 118 b) of theconductive stack structure 124, a portion of the conductive contactstructures 134 may be formed on or over a forward staircase structure(e.g., the first forward staircase structure 114 a, the second forwardstaircase structure 114 c) and an additional portion of the conductivecontact structures 134 may be formed on or over a reverse staircasestructure (e.g., the first reverse staircase structure 114 b, the secondreverse staircase structure 114 d). In additional embodiments, within atleast one of the stadium structures 118, each of the conductive contactstructures 134 may be formed on or over a forward staircase structure(e.g., the first forward staircase structure 114 a, the second forwardstaircase structure 114 c). In further embodiments, within at least oneof the stadium structures 118, each of the conductive contact structures134 may be formed on or over a reverse staircase structure (e.g., thefirst reverse staircase structure 114 b, the second reverse staircasestructure 114 d).

Conductive contact structures 134 formed on or over the same staircasestructure 114 (e.g., one of the first forward staircase structure 114 a,the first reverse staircase structure 114 b, the second forwardstaircase structure 114 c, and the second reverse staircase structure114 d) may be substantially uniformly (e.g., evenly) spaced apart fromone another, or may be non-uniformly (e.g., unevenly) spaced apart fromone another. Conductive contact structures 134 formed on or over thesame staircase structure 114 may be formed to be generally centrallypositioned (e.g., in at least the X-direction) on or over the steps 116associated therewith. Accordingly, distances between adjacent conductivecontact structures 134 located on or over the same staircase structure114 may vary in accordance with variance in the lengths (e.g., in theX-direction) of the adjacent steps 116 associated with the adjacentconductive contact structures 134. In addition, conductive contactstructures 134 formed on or over the same staircase structure 114 may besubstantially aligned with one another (e.g., not offset from oneanother in the Y-direction), or may be at least partially non-alignedwith one another (e.g., offset from one another in the Y-direction).

The conductive contact structures 134 may be formed of and include atleast one conductive material, such as a metal (e.g., tungsten,titanium, molybdenum, niobium, vanadium, hafnium, tantalum, chromium,zirconium, iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel,palladium, platinum, copper, silver, gold, aluminum), a metal alloy(e.g., a cobalt-based alloy, an iron-based alloy, a nickel-based alloy,an iron- and nickel-based alloy, a cobalt- and nickel-based alloy, aniron- and cobalt-based alloy, a cobalt- and nickel- and iron-basedalloy, an aluminum-based alloy, a copper-based alloy, a magnesium-basedalloy, a titanium-based alloy, a steel, a low-carbon steel, a stainlesssteel), a conductive metal-containing material (e.g., a conductive metalnitride, a conductive metal silicide, a conductive metal carbide, aconductive metal oxide), a conductively-doped semiconductor material(e.g., conductively-doped silicon, conductively-doped germanium,conductively-doped silicon germanium), or combinations thereof. Each ofthe conductive contact structures 134 may have substantially the samematerial composition, or at least one of the conductive contactstructures 134 may have a different material composition than at leastone other of the conductive contact structures 134.

With continued reference to FIG. 1F, the conductive routing structures136 may be coupled (e.g., attached, connected) to the conductive contactstructures 134 and at least one string driver device 138. The stringdriver device 138 may be formed of and include a plurality of switchingdevices (e.g., transistors). Suitable designs and configurations for theat least one string driver device 138 are well known in the art, and aretherefore not described in detail herein. The string driver device 138may, for example, underlie one or more portions (e.g., central portions,peripheral portions, combinations thereof) of the conductive stackstructure 124. The combination of the conductive contact structures 134and the conductive routing structures 136 may electrically connect theconductive structures 126 of one or more of the tiers 108 to the stringdriver device 138, facilitating application of voltages to theconductive structures 126 using the string driver device 138. Thecontinuous conductive paths across the conductive stack structure 124(e.g., from the first end 130 to the second, opposing end 132) providedby the configurations of the conductive structures 126 may permit anindividual (e.g., single) switching device (e.g., transistor) of thestring driver device 138 to drive voltages completely across (e.g., fromthe first end 130 to the second, opposing end 132) and/or in opposingdirections across (e.g., toward the first end 130 and toward the second,opposing end 132) an individual tier 108 electrically connected thereto.

The conductive routing structures 136 may extend from the conductivecontact structures 134, over one or more sections of the conductivestack structure 124, through one or more additional sections of theconductive stack structure 124, and to one or more of the string driverdevices 138. By way of non-limiting example, as shown in FIG. 1F, theconductive routing structures 136 may extend from conductive contactstructures 134, laterally over the middle section 122 of the conductivestack structure 124, longitudinally through insulating sections of thetiers 108 including the remaining portions 128 of the additionalinsulating structures 106 (FIG. 1D) and portions of the insulatingstructures 104, and to one or more of the string driver devices 138. Inaddition, each of the conductive routing structures 136 may extend tothe same string driver device 138, or at least one of the conductiverouting structures 136 may extend to a different string driver device138 than at least one other of the conductive routing structures 136.

The conductive routing structures 136 may be formed of and include atleast one conductive material, such as a metal (e.g., W, Ti, Mo, Nb, V,Hf, Ta, Cr, Zr, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Al), ametal alloy (e.g., a Co-based alloy, an Fe-based alloy, a Ni-basedalloy, an Fe- and Ni-based alloy, a Co- and Ni-based alloy, an Fe- andCu-based alloy, a Co- and Ni- and Fe-based alloy, an Al-based alloy, aCu-based alloy, a Mg-based alloy, a Ti-based alloy, a steel, alow-carbon steel, a stainless steel), a conductive metal-containingmaterial (e.g., a conductive metal nitride, a conductive metal silicide,a conductive metal carbide, a conductive metal oxide), aconductively-doped semiconductor material (e.g., conductively-dopedsilicon, conductively-doped germanium, conductively-doped silicongermanium), or combinations thereof. Each of the conductive routingstructures 136 may have substantially the same material composition, orat least one of the conductive routing structures 136 may have adifferent material composition than at least one other of the conductiverouting structures 136.

The conductive contact structures 134, the conductive routing structures136, and the string driver devices 138 may each independently be formedusing conventional processes (e.g., conventional deposition processes,conventional photolithography processes, conventional material removalprocesses) and conventional processing equipment, which are notdescribed in detail herein.

Thus, in accordance with embodiments of the disclosure, a method offorming a semiconductor device structure comprises forming a stackstructure comprising stacked tiers each comprising an insulatingstructure and an additional insulating structure longitudinally adjacentthe insulating structure. A masking structure is formed over a portionof the stack structure. Portions of the stacked tiers of the stackstructure not covered by the masking structure are removed to form atleast one staircase structure having steps comprising lateral ends ofthe stacked tiers. The masking structure is removed after forming the atleast one staircase structure. At least one opening is formed laterallyinward of the at least one staircase structure, the at least one openingextending through the stacked tiers and continuously across an entirelength of the at least one staircase structure. Portions of theadditional insulating structure of each of the stacked tiers arereplaced with at least one conductive material to form at least oneconductive structure in each of the stacked tiers, the at least oneconductive structure extending continuously from at least one of thesteps of the at least one staircase structure and around the at leastone opening to form at least one continuous conductive path extendingcompletely across each of the stacked tiers.

In addition, in accordance with additional embodiments of thedisclosure, a semiconductor device structure comprises stacked tierseach comprising at least one conductive structure and at least oneinsulating structure longitudinally adjacent the at least one conductivestructure, at least one staircase structure having steps comprisinglateral ends of the stacked tiers, and at least one opening extendingthrough the stacked tiers and continuously across an entire length ofthe at least one staircase structure. The at least one conductivestructure of each of the stacked tiers extends continuously from atleast one of the steps of the at least one staircase structure andaround the at least one opening to form at least one continuousconductive path extending completely across each of the stacked tiers.

One of ordinary skill in the art will appreciate that, in accordancewith additional embodiments of the disclosure, the features and featureconfigurations described above in relation to FIGS. 1A-1G may be readilyadapted to the design needs of different semiconductor devices (e.g.,different memory devices, such as different 3D NAND Flash memorydevices). By way of non-limiting example, FIG. 2 illustrates asemiconductor device structure 200 in accordance with another embodimentof the disclosure. The semiconductor device structure 200 may havesimilar features and functionalities to the semiconductor devicestructure 100 previously described. However, the semiconductor devicestructure 200 may, for example, include a relatively greater number oftiers 208, as well one or more additional features (e.g., additionalopenings, additional staircase structures, additional conductive contactstructures, additional conductive routing structures) and/or featureconfigurations (e.g., sizes, shapes, arrangements) to account for therelatively greater number of tiers 208. To avoid repetition, not allfeatures shown in FIG. 2 are described in detail herein. Rather, unlessdescribed otherwise below, features designated by a reference numeralthat is a 100 increment of the reference numeral of a feature describedpreviously in relation to one or more of FIGS. 1A-1G will be understoodto be substantially similar to the feature described previously.

As shown in FIG. 2, the semiconductor device structure 200 may include aconductive stack structure 224 exhibiting alternating insulatingstructures and conductive structures 226 arranged in tiers 208. Forclarity, the insulating structures of each of the tiers 208 are notdepicted FIG. 2. However, aside from variances in shape and size, theinsulating structures of the conductive stack structure 224 may besubstantially similar to, and may be formed and arranged insubstantially the same manner as, the insulating structures 104previously described in relation to the conductive stack structure 124.The conductive stack structure 224 may include a greater number of tiers208 than the number of the tiers 108 included in the conductive stackstructure 124 of the semiconductor device structure 100 previouslydescribed in relation to FIGS. 1F and 1G. For example, as shown in FIG.2, the conductive stack structure 224 may include twenty-one (21) tiers208. In additional embodiments, the conductive stack structure 224 mayinclude a different number of the tiers 208, such as greater thantwenty-one (21) tiers 208 or less than twenty-one (21) tiers 208.

The conductive stack structure 224 may include staircase structures 214,and openings 220 positioned laterally inward (e.g., in the Y-direction)of the staircase structures 214. In FIG. 2, for clarity in identifyingthe positions and dimensions of the openings 220, each of the openings220 is depicted as being filled with a structure. However, the openings220 may be substantially free of such structures (e.g., the structuresmay be absent from the openings 220). Alternatively, one or more of theopenings 220 may comprise filled openings including the depictedstructures therein. The structures may, for example, comprise insulatingstructures formed of and including at least one insulating material(e.g., an oxide material, such as silicon dioxide, phosphosilicateglass, borosilicate glass, borophosphosilicate glass, fluorosilicateglass, titanium dioxide, zirconium dioxide, hafnium dioxide, tantalumoxide, magnesium oxide, aluminum oxide, or combinations thereof; anitride material, such as silicon nitride; an oxynitride material, suchas silicon oxynitride; amphorous carbon).

As shown in FIG. 2, the conductive stack structure 224 includes multiple(e.g., more than one) staircase structures 214. The conductive stackstructure 224 may, for example, include multiple stadium structures 218each including opposing staircase structures 214. The multiple stadiumstructures 218 may be positioned in series and in parallel with oneanother. By way of non-limiting example, as shown in FIG. 2, theconductive stack structure 224 may include a first stadium structure 218a, a second stadium structure 218 b, a third stadium structure 218 c,and a fourth stadium structure 218 d. The first stadium structure 218 amay include a first forward staircase structure 214 a, and a firstreverse staircase structure 214 b that mirrors the first forwardstaircase structure 214 a. The second stadium structure 218 b may extendparallel (e.g., in the X-direction) to the first stadium structure 218a, and may include a second forward staircase structure 214 c, and asecond reverse staircase structure 214 d that mirrors the second forwardstaircase structure 214 c. The third stadium structure 218 c may extendin series (e.g., in the X-direction) to the first stadium structure 218a, and may include a third forward staircase structure 214 e, and athird reverse staircase structure 214 f that mirrors the third forwardstaircase structure 214 e. The fourth stadium structure 218 d may extendin parallel (in the X-direction) with the third stadium structure 218 cand in series (e.g., in the X-direction) to the second stadium structure218 b, and may include a fourth forward staircase structure 214 g, and afourth reverse staircase structure 214 h that mirrors the fourth forwardstaircase structure 214 g. The first stadium structure 218 a and thesecond stadium structure 218 b may be at least partially defined by endsof an upper group 209 a of the tiers 208 (e.g., tiers 208 positionedrelatively higher in the Z-direction), and may serve as redundant and/oralternative means of connecting to the tiers 208 of the upper group 209a. The third stadium structure 218 c and the fourth stadium structure218 d may be at least partially defined by ends of a lower group 209 bof the tiers 208 (e.g., tiers 208 positioned relatively lower in theZ-direction), and may serve as redundant and/or alternative means ofconnecting to the tiers 208 of the lower group 209 b.

In additional embodiments, the conductive stack structure 224 mayexhibit one or more of a different number and different configuration ofthe staircase structures 214. By way of non-limiting example, theconductive stack structure 224 may include only one (1) stadiumstructure 218 (e.g., only the first stadium structure 218 a, or only thesecond stadium structure 218 b) associated with (e.g., at leastpartially defined by ends of) the upper group 209 a of the tiers 208,may include only one (1) stadium structure 218 (e.g., only the thirdstadium structure 218 c, or only the fourth stadium structure 218 d)associated with the lower group 209 b of the tiers 208, may include morethan two (2) stadium structures 218 in parallel with one another andassociated with the upper group 209 a of the tiers 208, may include morethan two (2) stadium structures 218 in parallel with one another andassociated with the lower group 209 b of the tiers 208, may includeadditional stadium structures 218 in series with the first stadiumstructure 218 a and the third stadium structure 218 c, may includeadditional stadium structures 218 in series with the second stadiumstructure 218 b and the fourth stadium structure 218 d, may include oneor more forward staircase structures (e.g., one or more of the firstforward staircase structure 214 a, the second forward staircasestructure 214 c, the third forward staircase structure 214 e, and thefourth forward staircase structure 214 g) but not one or more reversestaircase structures (e.g., one or more of the first reverse staircasestructure 214 b, the second reverse staircase structure 214 d, the thirdreverse staircase structure 214 f, and the fourth reverse staircasestructure 214 h may be omitted), and/or may include one or more reversestaircase structures (e.g., one or more of the first reverse staircasestructure 214 b, the second reverse staircase structure 214 d, the thirdreverse staircase structure 214 f, and the fourth reverse staircasestructure 214 h) but not one or more forward staircase structures (e.g.,one or more of the first forward staircase structure 214 a, the secondforward staircase structure 214 c, the third forward staircase structure214 e, and the fourth forward staircase structure 214 g may be omitted).

As shown in FIG. 2, the openings 220 may longitudinally extend (e.g., inthe Z-direction) through the conductive stack structure 224, may bepositioned laterally inward (e.g., in the Y-direction) of the staircasestructures 214, and may continuously laterally extend (e.g., in theX-direction) across entire lengths of the staircase structures 214. Byway of non-limiting example, as shown in FIG. 2, the openings 220 mayextend completely through each of the tiers 208, may be positionedlaterally inwardly adjacent the stadium structures 218, and maycontinuously laterally extend across entire lengths of the stadiumstructures 218. A first opening 220 a may be positioned laterallybetween (e.g., in the Y-direction) the first stadium structure 218 a anda middle section 222 of the conductive stack structure 224, and maylaterally extend (e.g., in the X-direction) from a top of the firstforward staircase structure 214 a to a top of the first reversestaircase structure 214 b. A second opening 220 b may be positionedlaterally between (e.g., in the Y-direction) the second stadiumstructure 218 b and the middle section 222 of the conductive stackstructure 224, and may laterally extend parallel (e.g., in theX-direction) to the first opening 220 a from a top of the second forwardstaircase structure 214 c to a top of the second reverse staircasestructure 214 d. A third opening 220 c may be positioned laterallybetween (e.g., in the Y-direction) the third stadium structure 218 c andthe middle section 222 of the conductive stack structure 224, and maylaterally extend (e.g., in the X-direction) from a top of the thirdforward staircase structure 214 e to a top of the third reversestaircase structure 214 f. A fourth opening 220 d may be positionedlaterally between (e.g., in the Y-direction) the fourth stadiumstructure 218 d and the middle section 222 of the conductive stackstructure 224, and may laterally extend parallel (e.g., in theX-direction) to the third opening 220 c from a top of the fourth forwardstaircase structure 214 g to a top of the fourth reverse staircasestructure 214 h.

In additional embodiments, the conductive stack structure 224 mayinclude a different number of the openings 220. By way of non-limitingexample, at least one additional opening may be formed in the middlesection 222 of the conductive stack structure 224. The at least oneadditional opening may, for example, comprise a fifth opening positionedlaterally between the first opening 220 a and the second opening 220 band having substantially the same length as the first opening 220 a andthe second opening 220 b, and/or may comprise a sixth opening positionedlaterally between the third opening 220 c and the fourth opening 220 dand having substantially the same length as the third opening 220 c andthe fourth opening 220 d. The at least one additional opening may extendcompletely longitudinally through the middle section 222 of theconductive stack structure 224, and may continuously laterally extendacross the middle section 222 in parallel to the other openings 220.

As shown in FIG. 2, the conductive structures 226 may follow (e.g.,route along) lateral (e.g., side) surfaces of the conductive stackstructure 224. For example, the conductive structures 226 may extendinto and along outer lateral surfaces (e.g., peripheral lateralsurfaces) of the tiers 208, as well as into and along inner lateralsurfaces of the tiers 208 (e.g., lateral surfaces at least partiallydefined by the openings 220 longitudinally extending through the tiers208). For each of the tiers 208, the conductive structures 226 maylaterally extend to and around each of the openings 220 (e.g.,completely around ends of the openings 220, and completely across theportions of the middle section 222 of the conductive stack structure 224adjacent the openings 220) to form one or more continuous conductivepaths between a first end 230 of the conductive stack structure 224 anda second, opposing end 232 of the conductive stack structure 224. Thefirst end 230 and the second, opposing end 232 of the conductive stackstructure 224 may each be coupled to other components of a semiconductordevice (e.g., a memory device) including the semiconductor devicestructure 200, such as one or more memory cell arrays (e.g., verticalmemory cell arrays). In addition, portions of at least some of theconductive structures 226 may laterally extend (e.g., in theX-direction) to and at least partially define the staircase structures214 of the conductive stack structure 224 to form conductive contactregions (e.g., landing pad regions) for at least some of the tiers 208.For example, portions of at least some of the conductive structures 226of the upper group 209 a of the tiers 208 may extend to at leastpartially define the first stadium structure 218 a and the secondstadium structure 218 b, and portions of at least some of the conductivestructures 226 of the lower group 209 b of the tiers 208 may extend toat least partially define the third stadium structure 218 c and thefourth stadium structure 218 d. For each of the conductive structures226, portions thereof laterally extending to and at least partiallydefining one or more of the staircase structures 214 may be integral andcontinuous with other portions thereof laterally extending to and aroundthe openings 220 positioned laterally inward of (e.g., laterallyadjacent) the staircase structures 214. Each of the tiers 208 mayinclude multiple (e.g., more than one) conductive structures 226, or mayinclude a single (e.g., only one) conductive structure 226.

With continued reference to FIG. 2, conductive contact structures 234(e.g., conductive plugs, conductive vertical interconnects) may becoupled (e.g., attached, connected) to the conductive structures 226 ofthe tiers 208 at one or more of the staircase structures 214, andconductive routing structures 236 (e.g., conductive interconnects,conductive bridges) may be coupled to the conductive contact structures234 and to one or more string driver devices 238. The string driverdevices 238 may be formed of and include a plurality of switchingdevices (e.g., transistors). Suitable designs and configurations for thestring driver devices 238 are well known in the art, and are thereforenot described in detail herein. The string driver devices 238 may, forexample, underlie one or more portions (e.g., central portions,peripheral portions, combinations thereof) of the conductive stackstructure 224.

The conductive contact structures 234 and the conductive routingstructures 236 may electrically connect the conductive structures 226 ofthe tiers 208 to the string driver devices 238. By way of non-limitingexample, as shown in FIG. 2, a portion of the conductive contactstructures 234 and the conductive routing structures 236 mayelectrically connect the upper group 209 a of the tiers 208 to one ormore of the string driver devices 238 at one or more of the staircasestructures 214, and another portion of the conductive contact structures234 and the conductive routing structures 236 may electrically connectthe lower group 209 b of the tiers 208 to one or more of the stringdriver devices 238 at one or more other of the staircase structures 214.A portion of the conductive contact structures 234 and the conductiverouting structures 236 may be coupled to and extend between at least oneof the string driver devices 238 and steps 216 of one or more of thefirst stadium structure 218 a (e.g., steps 216 of the first forwardstaircase structure 214 a, and/or steps 216 of the first reversestaircase structure 214 b) and the second stadium structure 218 b (e.g.,steps 216 of the second forward staircase structure 214 c and/or steps216 of the second reverse staircase structure 214 d) to electricallyconnect the conductive structures 226 of at least some of the uppergroup 209 a of the tiers 208 to the string driver device 238. Inaddition, another portion of the conductive contact structures 234 andthe conductive routing structures 236 may be coupled to and extendbetween at least one string driver device 238 and steps 216 of one ormore of the third stadium structure 218 c (e.g., steps 216 of the thirdforward staircase structure 214 e, and/or steps 216 of the third reversestaircase structure 214 f) and the fourth stadium structure 218 d (e.g.,steps 216 of the fourth forward staircase structure 214 g, and/or steps216 of the fourth reverse staircase structure 214 h) to electricallyconnect the conductive structures 226 of at least some of the lowergroup 209 b of the tiers 208 to the string driver device 238. Thecontinuous conductive paths across the conductive stack structure 224(e.g., from the first end 230 to the second, opposing end 232) providedby the configurations of the conductive structures 226 may permit anindividual (e.g., single) switching device (e.g., transistor) of thestring driver device 238 to drive voltages completely across (e.g., fromthe first end 230 to the second, opposing end 232) and/or in opposingdirections across (e.g., toward the first end 230 and toward the second,opposing end 232) an individual tier 208 electrically connected thereto.

FIGS. 3A through 3F are simplified perspective (FIGS. 3A through 3E) andtop-down (FIG. 3F) views illustrating embodiments of a method of forminganother semiconductor device structure including a staircase structure,such as a memory array structure (e.g., a memory array block) for a 3Dnon-volatile memory device (e.g., a 3D NAND Flash memory device). Withthe description provided below, it will be readily apparent to one ofordinary skill in the art that the methods described herein may be usedin various devices. In other words, the methods of the disclosure may beused whenever it is desired to form a semiconductor device including astaircase structure.

Referring to FIG. 3A, a semiconductor device structure 300 may include astack structure 302 exhibiting an alternating sequence of insulatingstructures 304 and additional insulating structures 306 arranged intiers 308. Each of the tiers 308 may include one of the insulatingstructures 304 and one of the additional insulating structures 306. Thestack structure 302, including the tiers 308 of the insulatingstructures 304 and the additional insulating structures 306, may besubstantially similar to and may be formed in substantially the samemanner as the stack structure 102 previously described herein withreference to FIG. 1A. As shown in FIG. 3A, in some embodiments, thealternating sequence of the insulating structures 304 and the additionalinsulating structures 306 begins with one of the insulating structures304. In additional embodiments, the arrangement of the insulatingstructures 304 and the additional insulating structures 306 is switchedrelative to that depicted in FIG. 3A (e.g., the alternating sequence ofthe insulating structures 304 and the additional insulating structures306 begins with one of the additional insulating structures 306).

Referring to next to FIG. 3B, portions of the stack structure 302 (FIG.3A) (e.g., portions of one or more of the tiers 308) may be subjected toat least one material removal process (e.g., one or more of a trimmingprocess and a chopping process) to form a modified stack structure 310.The modified stack structure 310 may include one or more staircasestructures 312 each independently formed of and including one or moresteps 314. The steps 314 of the one or more staircase structures 312 maybe at least partially defined by exposed portions of one or more of thetiers 308 remaining following the at least one material removal process.

The modified stack structure 310 may include a single (e.g., only one)staircase structure 312, or may include multiple (e.g., more than one)staircase structures 312. In some embodiments, the modified stackstructure 310 includes multiple staircase structures 312. By way ofnon-limiting example, as shown in FIG. 3B, the modified stack structure310 may include a stadium structure 316 including a forward staircasestructure 312 a, and a reverse staircase structure 312 b that mirrorsthe forward staircase structure 312 a. In additional embodiments, themodified stack structure 310 may exhibit one or more of a differentnumber and different configuration of staircase structures 312. By wayof non-limiting example, the modified stack structure 310 may includetwo or more stadium structures 316 in series with one another, mayinclude one or more forward staircase structures (e.g., the forwardstaircase structure 312 a) but not one or more reverse staircasestructures (e.g., the reverse staircase structure 312 b may be omitted),may include one or more reverse staircase structures (e.g., reversestaircase structure 312 b) but not one or more forward staircasestructures (e.g., the forward staircase structure 312 a may be omitted),may include two or more forward staircase structures in series with oneanother, and/or may include two or more reverse staircase structures inseries with one another.

Each of the staircase structures 312 included in the modified stackstructure 310 may independently include a desired number of steps 314.The number of steps 314 included in each of the staircase structures 312may be substantially the same as (e.g., equal to) or may be differentthan (e.g., less than, or greater than) the number of tiers 308 in themodified stack structure 310. In some embodiments, the number of steps314 included in each of the staircase structures 312 is less than thenumber of tiers 308 in the modified stack structure 310. As anon-limiting example, as shown in FIG. 3B, each of the staircasestructures 312 (e.g., the forward staircase structure 312 a and thereverse staircase structure 312 b) may include ten (10) steps 314 atleast partially defined by ends of the eleven (11) tiers 308 (e.g.,tiers 308 a through 308 k) of the modified stack structure 310. Inadditional embodiments, one or more of the staircase structures 312 mayinclude a different number of steps 314 (e.g., less than ten (10) steps,greater than ten (10) steps). As a non-limiting example, if the modifiedstack structure 310 includes eleven (11) tiers 308, at least one of thestaircase structures 312 may include five (5) steps 314 at leastpartially defined by ends of a relatively lower group of the tiers 308(e.g., tier 308 f through tier 308 k), and at least one other of thestaircase structures 312 may include five (5) steps 314 at leastpartially defined by ends of a relatively higher group of the tiers 308(e.g., tiers 308 a through 308 e).

The dimensions of each of the steps 314 may independently be tailored todesired dimensions and positions of additional structures (e.g.,conductive structures, conductive contact structures) and/or openings(e.g., slots) to be formed in, on, over, and/or adjacent to the steps314 during subsequent processing of the semiconductor device structure300, as described in further detail below. As shown in FIG. 3B, each ofthe steps 314 may exhibit substantially the same width W₃ as themodified stack structure 310. In addition, each of the steps 312 mayexhibit substantially the same length, or at least one of the steps 314may exhibit a different length than at least one other of the steps 314.

The staircase structures 312 may be formed using conventional processes(e.g., conventional photolithography processes, conventional materialremoval processes) and conventional processing equipment, which are notdescribed in detail herein. By way of non-limiting example, aphotoresist structure may be formed on or over the stack structure 302(FIG. 3A), the photoresist structure may be photolithographicallyprocessed (e.g., photoexposed and developed) to remove at least onewidth thereof, one or more of the tiers 308 may be etched (e.g.,anisotropically etched, such as anisotropically dry etched) using theremaining portions of the photoresist structure as an etching mask, thephotoresist structure may be subjected to additional photolithographicprocessing to remove at least one additional width thereof, at leastanother group of the tiers 308 (e.g., the previously etched tier(s) 308and one or more additional tier(s) 308) may be etched using the newremaining portions of the photoresist structure as etching masks, and soon, until the modified stack structure 310 including the one or morestaircase structures 312 is formed.

Referring next to FIG. 3C, one or more openings 318 (e.g., slots,apertures, slits) may be formed in the modified stack structure 310. Theopenings 318 may extend through (e.g., completely through) the modifiedstack structure 310, and may divide (e.g., segment) the staircasestructures 312 (FIG. 3B) into additional staircase structures 320exhibiting relatively smaller widths than the staircase structures 312.The one or more openings 318 may laterally intervene (e.g., in theY-direction) between the additional staircase structures 320 and maycontinuously laterally extend (e.g., in the X-direction) across theentire lengths of the additional staircase structures 320.

Any desired number (e.g., quantity, amount) of openings 318 may beformed in the modified stack structure 310. The number of openings 318may correspond to desired numbers and configurations (e.g., shapes,sizes, positions) of the additional staircase structures 320. A single(e.g., only one) opening 318 may be formed longitudinally through (e.g.,in the Z-direction) and may extend continuously laterally across andbetween (e.g., in the X-direction) the staircase structures 312 (FIG.3B) (e.g., the forward staircase structure 312 a and the reversestaircase structure 312 b of the stadium structure 316) of the modifiedstack structure 310, or multiple (e.g., more than one) openings 318 maybe formed longitudinally through and may extend continuously laterallyin parallel across and between the staircase structures 312 of themodified stack structure 310. As shown in FIG. 3C, in some embodiments,three (3) openings 318 are formed in the modified stack structure 310.The three (3) openings 318 may at least partially define and separate(e.g., in the Y-direction) four (4) additional stadium structures 322. Afirst opening 318 a may be laterally disposed between a first additionalstadium structure 322 a and a second additional stadium structure 322 b,a second opening 318 b may be laterally disposed between the secondadditional stadium structure 322 b and a third additional stadiumstructure 322 c, and a third opening 318 c may be laterally disposedbetween the third additional stadium structure 322 c and a fourthadditional stadium structure 322 d. The first additional stadiumstructure 322 a may include a first forward staircase structure 320 aand a first reverse staircase structure 320 b. The second additionalstadium structure 322 b may include a second forward staircase structure320 c and a second reverse staircase structure 320 d. The thirdadditional stadium structure 322 c may include a third forward staircasestructure 320 e and a third reverse staircase structure 320 f. Thefourth additional stadium structure 322 d may include a fourth forwardstaircase structure 320 g and a fourth reverse staircase structure 320h. In additional embodiments, a different number of openings 318 (e.g.,less than three (3) openings 318, or more than three (3) openings 318)may be formed longitudinally through and continuously laterally acrossand between the staircase structures 312 (FIG. 3B). By way ofnon-limiting example, two (2) openings 318 may be formed in the modifiedstack structure 310 to at least partially define and separate three (3)additional stadium structures 322, or one (1) opening 318 may be formedin the modified stack structure 310 to at least partially define andseparate two (2) additional stadium structures 322.

The dimensions and spacing of the one or more openings 318 may beselected to provide desired dimensions (e.g., widths) to the additionalstaircase structures 320 (including steps 324 thereof), and to providedesired dimensions (e.g., widths) and spacing to conductive structuresto be formed using the openings 318, as described in further detailbelow. If more than one opening 318 is formed in the modified stackstructure 310, each of the openings 318 may exhibit substantially thesame dimensions (e.g., substantially the same width, length, andheight), or at least one of the openings 318 may exhibit one or moredifferent dimensions (e.g., a different width, a different length,and/or a different height) than at least one other of the openings 318.In some embodiments, each of the openings 318 exhibits substantially thesame dimensions. In addition, if more than two (2) openings 318 areformed in the modified stack structure 310, adjacent openings 318 may besubstantially uniformly (e.g., evenly) spaced apart from one another, ormay be non-uniformly (non-evenly) spaced apart from one another. In someembodiments, adjacent openings 318 are substantially uniformly spacedapart from one another. The openings 318 may be symmetricallydistributed across the modified stack structure 310, or may beasymmetrically distributed across the modified stack structure 310.

The openings 318 may be formed in the modified stack structure 310 usingone or more conventional material removal processes, which are notdescribed in detail herein. For example, one or more portions of themodified stack structure 310 may be subjected to at least one etchingprocess (e.g., at least one dry etching process, such as at least one ofan RIE process, a deep RIE process, a plasma etching process, a reactiveion beam etching process, and a chemically assisted ion beam etchingprocess; at least one wet etching process, such as at least one of ahydrofluoric acid etching process, a buffered hydrofluoric acid etchingprocess, and a buffered oxide etching process) to form the openings 318in the modified stack structure 310.

Referring to FIG. 3D, portions of the additional insulating structures306 (FIG. 3C) may be selectively removed, and may be replaced withconductive material to form a conductive stack structure 326. As shownin FIG. 3D, each of the tiers 308 of the conductive stack structure 326may include one or more conductive structures 328 (e.g., conductivegates, conductive plates) extending (e.g., in the X-direction and/or theY-direction) into lateral surfaces thereof. The one or more conductivestructures 328 of each tier 308 of the conductive stack structure 326may at least partially (e.g., substantially) laterally surroundremaining portions 330 (e.g., unremoved portions) of the additionalinsulating structures 306.

The conductive structures 328 may follow (e.g., route along) lateral(e.g., side) surfaces of the conductive stack structure 326. Forexample, the conductive structures 328 may extend into and along outerlateral surfaces (e.g., peripheral lateral surfaces) of the tiers 308,as well as into and along inner lateral surfaces of the tiers 308 (e.g.,lateral surfaces at least partially defined by the openings 318longitudinally extending through the tiers 308). Portions of at leastsome of the conductive structures 328 may laterally extend (e.g., in theX-direction) to and at least partially define the additional staircasestructures 320 of the conductive stack structure 326 to form conductivecontact regions (e.g., landing pad regions) for at least some of thetiers 308. In addition, in tiers 308 longitudinally below the additionalstaircase structures 320 (e.g., untrimmed tiers 308 and/or unchoppedtiers 308), the conductive structures 328 thereof may laterally extendto and may completely surround the openings 318 to form one or morecontinuous conductive paths between a first end 332 of the conductivestack structure 326 and a second, opposing end 334 of the conductivestack structure 326. The first end 332 and the second, opposing end 334of the conductive stack structure 326 may each be coupled to othercomponents of a semiconductor device (e.g., a memory device) includingthe semiconductor device structure 300, such as one or more memory cellarrays (e.g., vertical memory cell arrays).

As shown in FIG. 3D, the conductive stack structure 326 may includemultiple (e.g., more than one) conductive structures 328 in each of thetiers 308 defining the additional staircase structures 320. For example,for each of the tiers 308 defining the additional stadium structures322, at least one conductive structure 328 may at least partially definethe steps 324 of each of the forward staircase structures (e.g., each ofthe first forward staircase structure 320 a, the second forwardstaircase structure 320 c, the third forward staircase structure 320 e,and the fourth forward staircase structure 320 g), and at least oneother conductive structure 328 may at least partially define the steps324 of each of the reverse staircase structures (e.g., each of the firstreverse staircase structure 320 b, the second reverse staircasestructure 320 d, the third reverse staircase structure 320 f, and thefourth reverse staircase structure 320 h). The conductive structure 328at least partially defining the steps 324 of each of the forwardstaircase structures may extend laterally inward from the first end 332of the conductive stack structure 326, and may partially surround sidesof each of the openings 318 (e.g., the first opening 318 a, the secondopening 318 b, and the third opening 318 c). The other conductivestructure 328 at least partially defining the steps 324 of each of thereverse staircase structures may extend laterally inward from thesecond, opposing end 334 of the conductive stack structure 326, and mayalso partially surround sides of each of the openings 318. In someembodiments, for each of the tiers 308 defining the additional staircasestructures 320, a single (e.g., only one) conductive structure 328extends laterally inward from the first end 332 of the conductive stackstructure 326, and a single (e.g., only one) other conductive structure328 extends laterally inward from the second, opposing end 334 of theconductive stack structure 326. In additional embodiments, for one ormore of the tiers 308 defining the additional staircase structures 320,multiple (e.g., more than one) conductive structures 328 extendlaterally inward from the first end 332 of the conductive stackstructure 326, and/or multiple other conductive structures 328 extendlaterally inward from the second, opposing end 334 of the conductivestack structure 326. By way of non-limiting example, in some embodimentswherein the second opening 318 b is omitted (e.g., absent), one or moreof the tiers 308 may individually include at least two (2) of theconductive structures 328 extending laterally inward from the first end332, and/or at least two (2) of the conductive structures 328 extendinglaterally inward from the second, opposing end 334. In such embodiments,the at least two (2) of the conductive structures 328 extendinglaterally inward from the first end 332 may be separated (e.g.,isolated) from one another by a remaining portion of one of theadditional insulating structures 306 (FIG. 3C), and/or the at least two(2) of the conductive structures 328 extending laterally inward from thesecond, opposing end 334 may be separated (e.g., isolated) from oneanother by a remaining portion of one of the additional insulatingstructures 306 (FIG. 3C).

For tiers 308 (e.g., untrimmed tiers 308 and/or unchopped tiers 308)longitudinally below those defining the additional staircase structures320, each tier 308 may include a single (e.g., only one) conductivestructure 328, or one or more tiers 308 may individually includemultiple (e.g., more than one) conductive structures 328. In someembodiments, each of the tiers 308 longitudinally below those definingthe additional staircase structures 320 includes a single conductivestructure 328. The single conductive structure 328 may extend laterallyinward from the first end 332 and the second, opposing end 334 of theconductive stack structure 326 along outer lateral surfaces of theconductive stack structure 326, and may substantially completelysurround each of the openings 318 (e.g., each of the first opening 318a, the second opening 318 b, and the third opening 318 c) to form acontinuous conductive path extending from the first end 332 of theconductive stack structure 326 to the second, opposing end 334 of the ofthe conductive stack structure 326. In additional embodiments, one ormore of the tiers 308 longitudinally below those defining the additionalstaircase structures 320 individually include multiple conductivestructures 328. By way of non-limiting example, in some embodimentswherein the second opening 318 b is omitted (e.g., absent), one or moreof the tiers 308 longitudinally below those defining the additionalstaircase structures 320 may individually include at least two (2)conductive structures 328 extending laterally inward from the first end332 and the second, opposing end 334 of the conductive stack structure326. In such embodiments, the at least two (2) conductive structures 328may be separated (e.g., isolated) from one another by a remainingportion of one of the additional insulating structures 306 (FIG. 3C).

The dimensions and shapes of the conductive structures 328 may directlycorrespond to the dimensions and shapes of the removed portions of theadditional insulating structures 306 (FIG. 3C). A width (e.g., lateraldepth within the conductive stack structure 326) of each of theconductive structures 328 may be substantially uniform across the entirepath (e.g., route) of the conductive structure 328, or the width of atleast one of the conductive structures 328 may be substantiallynon-uniform (e.g., variable) across different portions of the path ofthe conductive structure 328. In some embodiments, portions of theconductive structures 328 laterally extending (e.g., in the X-direction)to and at least partially defining the additional staircase structures320 may exhibit substantially the same width as other portions (e.g.,insulating structure 304 portions) of the additional staircasestructures 320. In addition, each of the conductive structures 328 mayexhibit a different shape and at least one different dimension than eachother of the conductive structures 328, or at least one of theconductive structures 328 may exhibit one or more of substantially thesame shape and substantially the same dimensions as at least one otherof the conductive structures 328. By way of non-limiting example, asshown in FIG. 3D, conductive structures 328 of different tiers 308 mayexhibit different shapes and different dimensions (e.g., differentlengths associated with the locations of the different steps 324 of theadditional staircase structures 320) than one another, but conductivestructures 328 within the same tier 308 may exhibit substantially thesame shapes and substantially the same dimensions as one another (e.g.,conductive structures 328 within the same tier 308 may be mirror imagesof one another). In additional embodiments, conductive structures 328 oftwo or more different tiers 308 may exhibit substantially the sameshapes and substantially the same dimensions as one another. In furtherembodiments, conductive structures 328 within the same tier 308 mayexhibit one or more of a different shape and at least one differentdimension than one another.

The conductive structures 328 may be formed of and include at least oneconductive material, such as a metal, a metal alloy, a conductive metaloxide, a conductive metal nitride, a conductive metal silicide, aconductively-doped semiconductor material, or combinations thereof. Byway of non-limiting example, the conductive structures 328 may be formedof and include at least one of tungsten W, WN, Ni, Ta, TaN, TaSi, Pt,Cu, Ag, Au, Al, Mo, Ti, TiN, TiSi, TiSiN, TiAlN, MoN, Ir, IrO_(x), Ru,RuO_(x), and conductively-doped silicon. In some embodiments, theconductive structures 328 are formed of and include W.

The conductive structures 328 may be formed by selectively removingportions of the additional insulating structures 306 (FIG. 3C) relativeto the insulating structures 304 to form recessed regions laterallyextending into each of the tiers 308, and then at least partially (e.g.,substantially) filling the recessed regions with at least one conductivematerial. The recessed regions may be formed by subjecting the modifiedstack structure 310 (FIG. 3C) to at least one etching processing (e.g.,an isotropic etching process) employing an etch chemistry in which theinsulative material of the additional insulating structures 306 isselectively removed relative to that of the insulating structures 304.By way of non-limiting example, if the insulating structures 304 areformed of and include silicon dioxide (SiO₂), and the additionalinsulating structures 306 are formed of and include silicon nitride(Si₃N₄), the modified stack structure 310 may be exposed to an etchantcomprising phosphoric acid (H₃O₄P) to selectively remove portions of theadditional insulating structures 306 adjacent exposed lateral surfaces(e.g., exposed outer lateral surfaces, exposed inner lateral surfaces atleast partially defined by the openings 318) of the modified stackstructure 310. Thereafter, the conductive material may be formed (e.g.,delivered, deposited) within recessed regions to form the conductivestructures 328.

In additional embodiments, rather than selectively removing andreplacing portions of the additional insulating structures 306 (FIG. 3C)to form the conductive stack structure 326, portions of the insulatingstructures 304 may instead be selectively removed and replaced with aconductive material to form a conductive stack structure. Aside from thesequence (e.g., order) of the alternating conductive structures andinsulating structures of such a conductive stack structure anddifferences (if any) associated with material properties of theinsulating structures 304 as compared to those of the additionalinsulating structures 306, such a conductive stack structure may besubstantially similar to and may have little or no difference in termsof functionality and/or operability as compared to the conductive stackstructure 326 depicted in FIG. 3D.

Referring next to FIG. 3E, conductive contact structures 336 (e.g.,conductive plugs, conductive vertical interconnects) may be formed on,over, and/or within the one or more of the additional staircasestructures 320 of the conductive stack structure 326, conductive routingstructures 338 (e.g., conductive interconnects, conductive bridges) maybe formed on and between some of the conductive contact structures 336to electrically connect separate (e.g., discrete, isolated) conductivestructures 328 of one or more of the tiers 308, and additionalconductive routing structures 340 may be formed on and between other ofthe conductive contact structures 336 and at least one string driverdevice 342 to electrically connect the conductive structures 328 of oneor more of the tiers 308 to the string driver device 342. FIG. 3F is atop-down view of the semiconductor device structure 300 at theprocessing stage depicted in FIG. 3E.

The conductive contact structures 336 may be coupled to the conductivestructures 328 of the tiers 308 of the conductive stack structure 326 atthe steps 324 of the additional staircase structures 320. Each of thetiers 308 (e.g., each of the tiers 308 a through 308 k) may have one ormore of the conductive contact structures 336 coupled to the conductivestructures 328 thereof, or less than all of the tiers 308 (e.g., lessthan all of the tiers 308 a through 308 k, such as only tiers 308 bthrough 308 j) may have one or more of the conductive contact structures336 coupled to the conductive structures 328 thereof.

As shown in FIG. 3E, each of the tiers 308 having conductive contactstructures 336 coupled thereto may include at least two (2) firstconductive contact structures 336 a positioned to electrically connect(with the use of at least one of the conductive routing structures 338)separate conductive structures 328 of the tier 308. For example, foreach of the tiers 308 defining the additional stadium structures 322, atleast one first conductive contact structure 336 a may be coupled to atleast one conductive structure 328 of the tier 308 at a step 324 of atleast one forward staircase structure (e.g., one or more of the firstforward staircase structure 320 a, the second forward staircasestructure 320 c, the third forward staircase structure 320 e, and thefourth forward staircase structure 320 g), and at least one additionalfirst conductive contact structure 336 a may be coupled to at least oneother conductive structure 328 of the tier 308 at a step 324 of at leastone reverse staircase structure (e.g., one or more of the first reversestaircase structure 320 b, the second reverse staircase structure 320 d,the third reverse staircase structure 320 f, and the fourth reversestaircase structure 320 h). By way of non-limiting example, as depictedin FIG. 3E, for each of the tiers 308 defining the additional stadiumstructures 322, a first conductive contact structure 336 a may becoupled to a first conductive structure 328 of the tier 308 at a step324 of the fourth forward staircase structure 320 g of the fourthadditional stadium structure 322 d, and another first conductive contactstructure 336 a may be coupled to a second conductive structure 328 ofthe tier 308 at a step 324 of the fourth reverse staircase structure 320h of the fourth additional stadium structure 322 d.

In addition, as shown in FIG. 3E, each of the tiers 308 havingconductive contact structures 336 coupled thereto may include one ormore second conductive contact structures 336 b positioned toelectrically connect (with the use of at least one of the additionalconductive routing structures 340) the conductive structures 328 of thetier 308 to at least one of the string driver devices 342. For example,for each of the tiers 308 defining the additional stadium structures322, at least one second conductive contact structure 336 b may becoupled to at least one conductive structure 328 of the tier 308 at astep 324 of at least one of the additional staircase structures 320(e.g., one or more of the first forward staircase structure 320 a, thefirst reverse staircase structure 320 b, the second forward staircasestructure 320 c, the second reverse staircase structure 320 d, the thirdforward staircase structure 320 e, the third reverse staircase structure320 f, the fourth forward staircase structure 320 g, and the fourthreverse staircase structure 320 h). By way of non-limiting example, asdepicted in FIG. 3E, for each of the tiers 308 defining the additionalstadium structures 322, a second conductive contact structure 336 b maybe coupled to at least one of the conductive structures 328 of the tier308 at one or more of a step 324 of the first forward staircasestructure 320 a of the first additional stadium structure 322 a and astep 324 of the first reverse staircase structure 320 b of the firstadditional stadium structure 322 a.

The second conductive contact structures 336 b may be formed on or overa single (e.g., only one) additional staircase structure 320 of theconductive stack structure 326, or may be formed on or over multiple(e.g., more than one) additional staircase structures 320 of theconductive stack structure 326. By way of non-limiting example, as shownin FIGS. 3E and 3F, within at least one of the additional stadiumstructures 322 (e.g., one or more of the first additional stadiumstructure 322 a, the second additional stadium structure 322 b, thethird additional stadium structure 322 c, and the fourth additionalstadium structure 322 d) of the conductive stack structure 326, aportion of the second conductive contact structures 336 b may be formedon or over a forward staircase structure (e.g., the first forwardstaircase structure 320 a, the second forward staircase structure 320 c,the third forward staircase structure 320 e, the fourth forwardstaircase structure 320 g) and an additional portion of the secondconductive contact structures 336 b may be formed on or over a reversestaircase structure (e.g., the first reverse staircase structure 320 b,the second reverse staircase structure 320 d, the third reversestaircase structure 320 f, the fourth reverse staircase structure 320h). In additional embodiments, within at least one of the additionalstadium structures 322, each of the second conductive contact structures336 b may be formed on or over a forward staircase structure (e.g., thefirst forward staircase structure 320 a, the second forward staircasestructure 320 c, the third forward staircase structure 320 e, the fourthforward staircase structure 320 g). In further embodiments, within atleast one of the additional stadium structures 322, each of the secondconductive contact structures 336 b may be formed on or over a reversestaircase structure (e.g., the first reverse staircase structure 320 b,the second reverse staircase structure 320 d, the third reversestaircase structure 320 f, the fourth reverse staircase structure 320h).

Conductive contact structures 336 (e.g., first conductive contactstructures 336 a, second conductive contact structures 336 b) formed onor over the same additional staircase structure 320 may be substantiallyuniformly (e.g., evenly) spaced apart from one another, or may benon-uniformly (e.g., unevenly) spaced apart from one another. Conductivecontact structures 336 formed on or over the same additional staircasestructure 320 may be formed to be generally centrally positioned (e.g.,in at least the X-direction) on or over the steps 324 associatedtherewith. Accordingly, distances between adjacent conductive contactstructures 336 a located on or over the same additional staircasestructure 320 may vary in accordance with variance in the lengths (e.g.,in the X-direction) of the adjacent steps 324 associated with theadjacent conductive contact structures 336. In addition, conductivecontact structures 336 formed on or over the same additional staircasestructure 320 may be substantially aligned with one another (e.g., notoffset from one another in the Y-direction), or may be at leastpartially non-aligned with one another (e.g., offset from one another inthe Y-direction).

The conductive contact structures 336 may be formed of and include atleast one conductive material, such as a metal (e.g., tungsten,titanium, molybdenum, niobium, vanadium, hafnium, tantalum, chromium,zirconium, iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel,palladium, platinum, copper, silver, gold, aluminum), a metal alloy(e.g., a cobalt-based alloy, an iron-based alloy, a nickel-based alloy,an iron- and nickel-based alloy, a cobalt- and nickel-based alloy, aniron- and cobalt-based alloy, a cobalt- and nickel- and iron-basedalloy, an aluminum-based alloy, a copper-based alloy, a magnesium-basedalloy, a titanium-based alloy, a steel, a low-carbon steel, a stainlesssteel), a conductive metal-containing material (e.g., a conductive metalnitride, a conductive metal silicide, a conductive metal carbide, aconductive metal oxide), a conductively-doped semiconductor material(e.g., conductively-doped silicon, conductively-doped germanium,conductively-doped silicon germanium), or combinations thereof. Each ofthe conductive contact structures 336 may have substantially the samematerial composition, or at least one of the conductive contactstructures 336 may have a different material composition than at leastone other of the conductive contact structures 336.

With continued reference to FIGS. 3E and 3F, the conductive routingstructures 338 may be coupled (e.g., attached, connected) to and extendbetween portions of the conductive contact structures 336 (e.g.,portions of the first conductive contact structures 336 a). Theconductive routing structures 338 may form a conductive path between(e.g., electrically connect) electrically isolated conductive structures328 of one or more of the tiers 308 (FIG. 3E) of the conductive stackstructure 326. For example, for each of the tiers 308 defining theadditional stadium structures 322, the combination of the firstconductive contact structures 336 a and the conductive routingstructures 338 may electrically connect at least one conductivestructure 328 of the tier 308 located proximate the first end 332 of theconductive stack structure 326 to at least one other conductivestructure 328 of the tier 308 located proximate the second, opposing end334 of the conductive stack structure 326.

The conductive routing structures 338 may extend from a portion of theconductive contact structures 336 (e.g., a portion of the firstconductive contact structures 336 a) located proximate the first end 332of the conductive stack structure 326, over one or more sections of theconductive stack structure 326, and to other portions of the conductivecontact structures 336 (e.g., another portion of the first conductivecontact structures 336 a) located proximate the second, opposing end 334of the conductive stack structure 326. For example, for each of thetiers 308 defining the additional stadium structures 322, at least oneconductive routing structure 338 extends from at least one firstconductive contact structure 336 a positioned on or over a step 324 ofat least one forward staircase structure (e.g., one or more of the firstforward staircase structure 320 a, the second forward staircasestructure 320 c, the third forward staircase structure 320 e, and thefourth forward staircase structure 320 g) to at least one other firstconductive contact structure 336 a positioned on or over a step 324 ofat least one reverse staircase structure (e.g., one or more of the firstreverse staircase structure 320 b, the second reverse staircasestructure 320 d, the third reverse staircase structure 320 f, and thefourth reverse staircase structure 320 h). By way of non-limitingexample, as shown in FIGS. 3E and 3F, for each of the tiers 308 definingthe additional stadium structures 322, a conductive routing structure338 may extend from a first conductive contact structure 336 a locatedon or over a step 324 of the fourth forward staircase structure 320 g ofthe fourth additional stadium structure 322 d to another firstconductive contact structure 336 a located on or over a step 324 of thefourth reverse staircase structure 320 h of the fourth additionalstadium structure 322 d.

With continued reference to FIG. 3E, the additional conductive routingstructures 340 may be coupled (e.g., attached, connected) to portions ofthe conductive contact structures 336 (e.g., portions of the secondconductive contact structures 336 b) and at least one string driverdevice 342. The string driver device 342 may be formed of and include aplurality of switching devices (e.g., transistors). Suitable designs andconfigurations for the string driver device 342 are well known in theart, and are therefore not described in detail herein. The string driverdevice 342 may, for example, underlie one or more portions (e.g.,central portions, peripheral portions, combinations thereof) of theconductive stack structure 326. The combination of the conductivecontact structures 336 (e.g., the first conductive contact structures336 a and the second conductive contact structures 336 b), theconductive routing structures 338, and the additional conductive routingstructures 340 may electrically connect the conductive structures 328 ofone or more of the tiers 308 to the string driver device 342,facilitating application of voltages to the conductive structures 328using the string driver device 342. The continuous conductive pathsacross the conductive stack structure 326 (e.g., from the first end 332to the second, opposing end 334) provided by the configurations andpositions of the conductive structures 328, the conductive contactstructures 336 (e.g., the first conductive contact structures 336 a),and the conductive routing structures 338 may permit an individual(e.g., single) switching device (e.g., transistor) of the string driverdevice 342 to drive voltages completely across (e.g., from the first end332 to the second, opposing end 334) and/or in opposing directionsacross (e.g., toward the first end 332 and toward the second, opposingend 334) an individual tier 308 electrically connected thereto.

The additional conductive routing structures 340 may extend from theconductive contact structures 336 (e.g., the second conductive contactstructures 336 b), over one or more sections of the conductive stackstructure 326, through one or more additional sections of the conductivestack structure 326, and to one or more of the string driver devices342. By way of non-limiting example, as shown in FIG. 3E, the additionalconductive routing structures 340 may extend from the second conductivecontact structures 336 b, laterally over a middle section of theconductive stack structure 326, longitudinally through insulatingsections of the tiers 308 including the remaining portions 330 of theadditional insulating structures 306 (FIG. 3C) and portions of theinsulating structures 304, and to the string driver devices 342. Inaddition, each of the additional conductive routing structures 340 mayextend to the same string driver device 342, or at least one of theadditional conductive routing structures 340 may extend to a differentstring driver device 342 than at least one other of the additionalconductive routing structures 340.

The conductive routing structures 338 and the additional conductiverouting structures 340 may be formed of and include at least oneconductive material, such as a metal (e.g., W, Ti, Mo, Nb, V, Hf, Ta,Cr, Zr, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Al), a metalalloy (e.g., a Co-based alloy, an Fe-based alloy, a Ni-based alloy, anFe- and Ni-based alloy, a Co- and Ni-based alloy, an Fe- and Cu-basedalloy, a Co- and Ni- and Fe-based alloy, an Al-based alloy, a Cu-basedalloy, a Mg-based alloy, a Ti-based alloy, a steel, a low-carbon steel,a stainless steel), a conductive metal-containing material (e.g., aconductive metal nitride, a conductive metal silicide, a conductivemetal carbide, a conductive metal oxide), a conductively-dopedsemiconductor material (e.g., conductively-doped silicon,conductively-doped germanium, conductively-doped silicon germanium), orcombinations thereof. Each of the conductive routing structures 338 andeach of the additional conductive routing structures 340 may havesubstantially the same material composition, or one or more of theconductive routing structures 338 and the additional conductive routingstructures 340 may have a different material composition than one ormore other of the conductive routing structures 338 and the additionalconductive routing structures 340.

The conductive contact structures 336, the conductive routing structures338, the additional conductive routing structures 340, and the stringdriver devices 342 may each independently be formed using conventionalprocesses (e.g., conventional deposition processes, conventionalphotolithography processes, conventional material removal processes) andconventional processing equipment, which are not described in detailherein.

Thus, in accordance with embodiments of the disclosure, a method offorming a semiconductor device structure comprises forming a stackstructure comprising stacked tiers each comprising an insulatingstructure and an additional insulating structure longitudinally adjacentthe insulating structure. Portions of the stacked tiers of the stackstructure are removed to form at least one stadium structure comprisingopposing staircase structures. At least one opening is formed to extendthrough the stacked tiers and continuously across an entire length ofthe at least one stadium structure to form additional stadium structureseach comprising additional opposing staircase structures having stepscomprising lateral ends of the stacked tiers. Portions of the additionalinsulating structure of each of the stacked tiers are replaced with atleast one conductive material to form conductive structures in each ofthe stacked tiers. The conductive contact structures are coupled to theconductive structures of the stacked tiers at steps of the additionalopposing staircase structures of at least one of the additional stadiumstructure. Conductive routing structures are coupled to and completelybetween pairs of the conductive contact structures to form at least onecontinuous conductive path extending completely across each of thestacked tiers.

In addition, in accordance with additional embodiments of thedisclosure, a semiconductor device structure comprises stacked tierseach comprising conductive structures and insulating structureslongitudinally adjacent the conductive structures; stadium structureseach comprising opposing staircase structures having steps comprisinglateral ends of the stacked tiers, at least one opening laterallyintervening between at least two of the stadium structures; the at leastone opening extending through the stacked tiers and continuously acrossentire lengths of the at least two stadium structures; conductivecontact structures coupled to the conductive structures of the stackedtiers at steps of the opposing staircase structures of at least one ofthe stadium structures; and conductive routing structures coupled to andextending completely between pairs of the conductive contact structuresto form at least one continuous conductive path extending completelyacross each of the stacked tiers.

One of ordinary skill in the art will appreciate that, in accordancewith additional embodiments of the disclosure, the features and featureconfigurations described above in relation to FIGS. 3A-3F may be readilyadapted to the design needs of different semiconductor devices (e.g.,different memory devices, such as different 3D NAND Flash memorydevices). By way of non-limiting example, FIG. 4 illustrates asemiconductor device structure 400 in accordance with another embodimentof the disclosure. The semiconductor device structure 400 may havesimilar features and functionalities to the semiconductor devicestructure 300 previously described. However, the semiconductor devicestructure 400 may, for example, include a relatively greater number oftiers 408, as well one or more additional features (e.g., additionalopenings, additional staircase structures, additional conductive contactstructures, additional conductive routing structures) and/or featureconfigurations (e.g., sizes, shapes, arrangements) to account for therelatively greater number of tiers 408. To avoid repetition, not allfeatures shown in FIG. 4 are described in detail herein. Rather, unlessdescribed otherwise below, features designated by a reference numeralthat is a 100 increment of the reference numeral of a feature describedpreviously in relation to one or more of FIGS. 3A-3F will be understoodto be substantially similar to the feature described previously.

As shown in FIG. 4, the semiconductor device structure 400 may include aconductive stack structure 426 exhibiting an alternating sequence ofinsulating structures and conductive structures 428 arranged in tiers408. For clarity, the insulating structures of each of the tiers 408 arenot depicted FIG. 4. However, aside from variances in shape and size,the insulating structures of the conductive stack structure 426 may besubstantially similar to, and may be formed and arranged insubstantially the manner as, the insulating structures 304 previouslydescribed in relation to the conductive stack structure 326. Theconductive stack structure 426 may include a greater number of tiers 408than the number of the tiers 308 included in the conductive stackstructure 326 of the semiconductor device structure 300 previouslydescribed in relation to FIGS. 3E and 3F.

The conductive stack structure 426 may include multiple (e.g., more thanone) staircase structures 420. For example, the conductive stackstructure 426 may include multiple stadium structures 422 each includingopposing staircase structures 420. The multiple stadium structures 422may be positioned in series and in parallel with one another. By way ofnon-limiting example, as shown in FIG. 4, the conductive stack structure426 may include a first stadium structure 422 a, a second stadiumstructure 422 b, a third stadium structure 422 c, a fourth stadiumstructure 422 d, a fifth stadium structure 422 e, a sixth stadiumstructure 422 f, a seventh stadium structure 422 g, and an eighthstadium structure 422 h. The first stadium structure 422 a may include afirst forward staircase structure 420 a, and a first reverse staircasestructure 420 b that mirrors the first forward staircase structure 420a. The second stadium structure 422 b may extend parallel (e.g., in theX-direction) to the first stadium structure 422 a, and may include asecond forward staircase structure 420 c, and a second reverse staircasestructure 420 d that mirrors the second forward staircase structure 420c. The third stadium structure 422 c may also extend parallel (e.g., inthe X-direction) to the first stadium structure 422 a, and may include athird forward staircase structure 420 e, and a third reverse staircasestructure 420 f that mirrors the third forward staircase structure 420e. The fourth stadium structure 422 d may also extend parallel (e.g., inthe X-direction) to the first stadium structure 422 a, and may include afourth forward staircase structure 420 g, and a fourth reverse staircasestructure 420 h that mirrors the fourth forward staircase structure 420g. The fifth stadium structure 422 e may extend in series (e.g., in theX-direction) to the first stadium structure 422 a, and may include afifth forward staircase structure 420 i, and a fifth reverse staircasestructure 420 j that mirrors the fifth forward staircase structure 420i. The sixth stadium structure 422 f may extend in parallel (in theX-direction) with the fifth stadium structure 422 e and in series (e.g.,in the X-direction) to the second stadium structure 422 b, and mayinclude a sixth forward staircase structure 420 k, and a sixth reversestaircase structure 420 l that mirrors the sixth forward staircasestructure 420 k. The seventh stadium structure 422 g may extend inparallel (in the X-direction) with the fifth stadium structure 422 e andin series (e.g., in the X-direction) to the third stadium structure 422c, and may include a seventh forward staircase structure 420 m, and aseventh reverse staircase structure 420 n that mirrors the seventhforward staircase structure 420 m. The eighth stadium structure 422 hmay extend in parallel (in the X-direction) with the fifth stadiumstructure 422 e and in series (e.g., in the X-direction) to the fourthstadium structure 422 d, and may include an eighth forward staircasestructure 420 o, and an eighth reverse staircase structure 420 p thatmirrors the eighth forward staircase structure 420 o. Each of thestadium structures 422 a through 422 d and 422 f through 422 h may be atleast partially defined by ends of an upper group 409 a of the tiers 408(e.g., tiers 408 positioned relatively higher in the Z-direction), andmay serve as redundant and/or alternative means of connecting to thetiers 408 of the upper group 409 a. The fifth stadium structure 422 emay be at least partially defined by ends of a lower group 409 b of thetiers 408 (e.g., tiers 408 positioned relatively lower in theZ-direction), and may serve as redundant and/or alternative means ofconnecting to the tiers 408 of the lower group 409 b.

In additional embodiments, the conductive stack structure 426 mayexhibit one or more of a different number and different configuration ofstaircase structures 420. By way of non-limiting example, the conductivestack structure 426 may include a different number (e.g., more or less)of stadium structures 422 associated with (e.g., at least partiallydefined by ends of) the upper group 409 a of the tiers 408, may includeone or more additional stadium structures 422 associated with the lowergroup 409 b of the tiers 408, may include one or more additional stadiumstructures in series with one or more of the stadium structures 422, mayinclude one or more forward staircase structures but not one or morereverse staircase structures, and/or may include one or more reversestaircase structures but not one or more forward staircase structures.

With continued reference to FIG. 4, the conductive stack structure 426may include multiple (e.g., more than one) openings 418 therein. Theopenings 418 may longitudinally extend (e.g., in the Z-direction)through the conductive stack structure 426, may laterally intervene(e.g., in the Y-direction) between the staircase structures 420, and maycontinuously laterally extend (e.g., in the X-direction) across theentire lengths of the staircase structures 420. By way of non-limitingexample, as shown in FIG. 4, the openings 418 may extend completelythrough each of the tiers 408, may be positioned laterally adjacent thestadium structures 422, and may continuously laterally extend acrossentire lengths of the stadium structures 422. A first opening 418 a maybe disposed between (e.g., in the Y-direction) and extend across (e.g.,in the X-direction) entire lengths of the first stadium structure 422 aand the second stadium structure 422 b. A second opening 418 b mayextend in parallel with the first opening 418 a, and may be disposedbetween and extend across entire lengths of the second stadium structure422 b and the third stadium structure 422 c. A third opening 418 c mayextend in parallel with the first opening 418 a, and may be disposedbetween and extend across entire lengths of the third stadium structure422 c and the fourth stadium structure 422 d. A fourth opening 418 d mayextend in series with the first opening 418 a, and may be disposedbetween and extend across entire lengths of the fifth stadium structure422 e and the sixth stadium structure 422 f A fifth opening 418 e mayextend in parallel with the fifth stadium structure 422 e and serieswith the second opening 418 b, and may be disposed between and extendacross entire lengths of the sixth stadium structure 422 f and theseventh stadium structure 422 g. A sixth opening 418 f may extend inparallel with the fifth stadium structure 422 e and series with thethird opening 418 c, and may be disposed between and extend acrossentire lengths of the seventh stadium structure 422 g and the eighthstadium structure 422 h. In additional embodiments, the conductive stackstructure 426 may include a different number of the openings 418 (e.g.,less than six (6) openings 418, or more than six (6) openings 418).

As shown in FIG. 4, the conductive structures 428 may follow (e.g.,route along) lateral (e.g., side) surfaces of the conductive stackstructure 426. For example, the conductive structures 428 may extendinto and along outer lateral surfaces (e.g., peripheral lateralsurfaces) of the tiers 408, as well as into and along inner lateralsurfaces of the tiers 408 (e.g., lateral surfaces at least partiallydefined by the openings 418 longitudinally extending through the tiers408). The conductive structures 428 of the upper group 409 a of thetiers 408 may laterally extend to and partially (e.g., incompletely)around the openings 418, and may at least partially define a portion ofthe staircase structures 420 of the conductive stack structure 326. Forexample, as shown in FIG. 4, one or more (e.g., each) tiers 408 of theupper group 409 a of the tiers 408 may individually include multiple(e.g., more than one) conductive structures 428 that laterally extend toand partially around the openings 418, and that partially define thestadium structures 422 a through 422 d and 422 f through 422 h. Themultiple conductive structures 428 of each of the tiers 408 defining thestadium structures 422 a through 422 d and 422 f through 422 h may formdiscontinuous (e.g., segmented) conductive paths between a first end 432of the conductive stack structure 426 and a second, opposing end 434 ofthe conductive stack structure 426. The first end 432 and the second,opposing end 434 of the conductive stack structure 426 may each becoupled to other components of a semiconductor device (e.g., a memorydevice) including the semiconductor device structure 400, such as one ormore memory cell arrays (e.g., vertical memory cell arrays). Each of thetiers 408 of the upper group 409 a of the tiers 408 may include multiple(e.g., more than one) conductive structures 428, or at least one of thetiers 408 of the upper group 409 a may include a single (e.g., only one)conductive structure 428. In addition, the conductive structures 428 ofthe lower group 409 b of the tiers 408 may laterally extend to andcompletely around the openings 418, and may at least partially defineanother portion of the staircase structures 420 of the conductive stackstructure 326. For example, as shown in FIG. 4, one or more (e.g., each)tiers 408 of the lower group 409 b of the tiers 408 may individuallyinclude one or more conductive structures 428 that laterally extend toand completely around the openings 418, and that partially define thefifth stadium structure 422 e. The one or more conductive structures 428of each of the tiers 408 defining the fifth stadium structure 422 e mayform one or more continuous conductive paths between the first end 432of the conductive stack structure 426 and the second, opposing end 434of the conductive stack structure 426. Each of the tiers 408 of thelower group 409 b of the tiers 408 may include single (e.g., only one)conductive structure 428, or at least one of the tiers 408 of the lowergroup 409 b may include multiple (e.g., more than one) conductivestructures 428.

With continued reference to FIG. 4, first conductive contact structures436 a (e.g., conductive plugs, conductive vertical interconnects) may becoupled (e.g., attached, connected) to at least a portion the conductivestructures 428 of the upper group 409 a of the tiers 408 at opposingsteps 424 of one or more of the stadium structures 422. For example, foreach of the tiers 408 of the upper group 409 a of the tiers 408 definingthe stadium structures 422 a through 422 d, at least one firstconductive contact structure 436 a may be coupled to at least oneconductive structure 428 of the tier 408 at a step 424 of at least oneforward staircase structure (e.g., one or more of the first forwardstaircase structure 420 a, the second forward staircase structure 420 c,the third forward staircase structure 420 e, and the fourth forwardstaircase structure 420 g), and at least one additional first conductivecontact structure 436 a may be coupled to at least one other conductivestructure 428 of the tier 408 at an opposing step 424 of at least onereverse staircase structure (e.g., one or more of the first reversestaircase structure 420 b, the second reverse staircase structure 420 d,the third reverse staircase structure 420 f, and the fourth reversestaircase structure 420 h). In addition, for each of the tiers 408 ofthe upper group 409 a of the tiers 408 defining the stadium structures422 f through 422 h, at least one additional first conductive contactstructure 436 a may be coupled to at least one conductive structure 428of the tier 408 at a step 424 of at least one forward staircasestructure (e.g., one or more of the sixth forward staircase structure420 k, the seventh forward staircase structure 420 m, and the eighthforward staircase structure 420 o), and at least one further firstconductive contact structure 436 a may be coupled to at least one otherconductive structure 428 of the tier 408 at an opposing step 424 of atleast one reverse staircase structure (e.g., one or more of the sixthreverse staircase structure 420 l, the seventh reverse staircasestructure 420 n, and the eighth reverse staircase structure 420 p). Byway of non-limiting example, as shown in FIG. 4, for each of the tiers408 of the upper group 409 a of the tiers 408 defining the stadiumstructures 422 a through 422 d and 422 f through 422 h, two (2) firstconductive contact structures 436 a may be coupled to conductivestructures 428 of the tier 408 at opposing steps 424 of the fourthstadium structure 422 d (e.g., opposing steps 424 of the fourth forwardstaircase structure 420 g and the fourth reverse staircase structure 402h), and two (2) additional first conductive contact structures 436 a maybe coupled to conductive structures 428 of the tier 408 at opposingsteps 424 of the eighth stadium structure 422 h (e.g., opposing steps424 of the eighth forward staircase structure 420 o and the eighthreverse staircase structure 402 p).

In addition, as shown in FIG. 4, second conductive contact structures436 b may be coupled (e.g., attached, connected) to at least a portionof the conductive structures 428 of each of the upper group 409 a of thetiers 408 and the lower group of the tiers 408 at steps 424 of thestadium structures 422. For example, for each of the tiers 408 of theupper group 409 a of the tiers 408 defining the stadium structures 422 athrough 422 d and 422 f through 422 h at least one second conductivecontact structure 436 b may be coupled to at least one conductivestructure 428 of the tier 408 at a step 424 of at least one of thestadium structures 422 a through 422 d and 422 f through 422 h. By wayof non-limiting example, for each of the tiers 408 of the upper group409 a of the tiers 408 defining the stadium structures 422 a through 422d and 422 f through 422 h, at least one second conductive contactstructure 436 b may be coupled to at least one conductive structure 428of the tier 408 at one or more steps 424 of the first stadium structure422 a (e.g., a step 424 of the first forward staircase structure 420 a,and/or a step 424 of the first reverse staircase structure 420 b). Inaddition, for each of the tiers 408 of the lower group 409 b definingthe fifth stadium structure 422 e at least one additional secondconductive contact structure 436 b may be coupled to at least oneconductive structure 428 of the tier 408 at a step 424 of the fifthstadium structure 422 e. By way of non-limiting example, for each of thetiers 408 of the lower group 409 b of the tiers 408 defining the fifthstadium structure 422 e, at least one second conductive contactstructure 436 b may be coupled to at least one conductive structure 428of the tier 408 at one or more steps 424 of the fifth stadium structure422 e (e.g., a step 424 of fifth forward staircase structure 420 i,and/or a step 424 of the fifth reverse staircase structure 420 j).

With continued reference to FIG. 4, conductive routing structures 438may be coupled (e.g., attached, connected) to and extend between thefirst conductive contact structures 436 a. The conductive routingstructures 438 may form conductive paths between (e.g., electricallyconnect) electrically isolated conductive structures 428 of the tiers408 of the upper group 409 a of the tiers 408. For each of the tiers 408of the upper group 409 a defining the stadium structures 422 a through422 d and 422 f through 422 h, the combination of the first conductivecontact structures 436 a and the conductive routing structures 438 mayelectrically connect a least a portion of conductive structures 428 ofthe tier 408 to form a continuous conductive path extending from thefirst end 432 of the conductive stack structure 426 to the second,opposing end 434 of the conductive stack structure 426. For example, foreach of the tiers 408 defining the stadium structures 422 a through 422d, at least one conductive routing structure 438 may extend from atleast one first conductive contact structure 436 a located on or over astep 424 of at least one forward staircase structure (e.g., one or moreof the first forward staircase structure 420 a, the second forwardstaircase structure 420 c, the third forward staircase structure 420 e,and the fourth forward staircase structure 420 g) to at least one otherfirst conductive contact structure 436 a positioned on or over a step424 of at least one reverse staircase structure (e.g., one or more ofthe first reverse staircase structure 420 b, the second reversestaircase structure 420 d, the third reverse staircase structure 420 f,and the fourth reverse staircase structure 420 h). In addition, for eachof the tiers 408 defining the stadium structures 422 f through 422 h, atleast one conductive routing structure 438 may extend from at least onefirst conductive contact structure 436 a positioned on or over a step424 of at least one forward staircase structure (e.g., one or more ofthe sixth forward staircase structure 420 k, the seventh forwardstaircase structure 420 m, and the eighth forward staircase structure420 o) to at least one other first conductive contact structure 436 apositioned on or over a step 424 of at least one reverse staircasestructure (e.g., one or more of the sixth reverse staircase structure420 l, the seventh reverse staircase structure 420 n, and the eighthreverse staircase structure 420 p). By way of non-limiting example, asshown in FIG. 4, for each of the tiers 408 of the upper group 409 adefining the stadium structures 422 a through 422 d and 422 f through422 h, a conductive routing structure 438 may be coupled to the firstconductive contact structures 436 a located on or over opposing steps424 of the fourth stadium structure 422 d (e.g., on or over opposingsteps 424 of the fourth forward staircase structure 420 g and the fourthreverse staircase structure 420 h), and another conductive routingstructure 438 may be coupled to the first conductive contact structures436 a located on or over opposing steps 424 of the eighth stadiumstructure 422 h (e.g., on or over opposing steps 424 of the eighthforward staircase structure 420 o and the eighth reverse staircasestructure 420 p).

As previously described, tiers 408 (e.g., at least the lower group 409 bof the tiers 408) of the conductive stack structure 426 longitudinallybelow the tiers 408 defining the stadium structures 422 a through 422 dand 422 f through 422 h may already exhibit continuous conductive pathsextending from the first end 432 of the conductive stack structure 426to the second, opposing end 434 of the conductive stack structure 426due to the portions of the conductive structures 428 thereof that extendto and completely around the openings 418. Accordingly, with the use ofthe first conductive contact structures 436 a and the conductive routingstructures 438, each of the tiers 408 of the conductive stack structure426 may exhibit at least one continuous conductive path extending fromthe first end 432 of the conductive stack structure 426 to the second,opposing end 434 of the conductive stack structure 426.

As shown in FIG. 4, additional conductive routing structures 440 may becoupled (e.g., attached, connected) to and extend between the secondconductive contact structures 436 b and at least one string driverdevice 442. The additional conductive routing structures 440 may formconductive paths between (e.g., electrically connect) the string driverdevice 442 and at least some of the conductive structures 428 of each ofthe upper group 409 a of the tiers 408 and the lower group 409 b of thetiers 408. For example, for each of the tiers 408 of the upper group 409a defining the stadium structures 422 a through 422 d and 422 f through422 h, at least one additional conductive routing structure 440 mayextend from at least one second conductive contact structure 436 blocated on or over a step 424 of one or more of the stadium structures422 a through 422 d and 422 f through 422 h (e.g., a step 424 of one ormore of the forward staircase structures 420 a, 420 c, 420 e, 420 g, 420k, 420 m, and 420 o, and/or a step 424 of one or more of the reversestaircase structures 420 b, 420 d, 420 f, 420 h, 4201, 420 n, and 420 p)to at least one of the string driver devices 442. In addition, for eachof the tiers 408 of the lower group 409 b defining the fifth stadiumstructure 422 e, at least one other additional conductive routingstructure 440 may extend from a step 424 of the fifth stadium structure422 e (e.g., a step 424 of the fifth forward staircase structure 420 i,and/or a step 424 of the fifth reverse staircase structure 420 j) to atleast one of the string driver devices 442.

The conductive paths between the one or more string driver devices 442and the conductive structures 428 of the tiers 408 provided by thesecond conductive contact structures 436 b and additional conductiverouting structures 440 may facilitate application of voltages to theconductive structures 428 using the string driver devices 442. In turn,the continuous conductive paths across the conductive stack structure426 (e.g., from the first end 432 to the second, opposing end 434)provided by the configurations and positions of the conductivestructures 428, the first conductive contact structures 436 a, and theconductive routing structures 438 may permit an individual (e.g.,single) switching device (e.g., transistor) of the string driver device442 to drive voltages completely across (e.g., from the first end 432 tothe second, opposing end 434) and/or in opposing directions across(e.g., toward the first end 432 and toward the second, opposing end 434)an individual tier 408 electrically connected thereto.

In additional embodiments, one or more of the conductive routingstructures 438 and the additional conductive routing structures 440 maybe configured and/or positioned differently than depicted in FIG. 4. Byway of non-limiting example, FIG. 5 shows an embodiment of asemiconductor device structure 500 including conductive routingstructures 538 exhibiting different configurations than the conductiverouting structures 438 (FIG. 4). The semiconductor device structure 500may be substantially similar to the semiconductor device structure 400,except for the conductive routing structures 538 and the associatedpositions of at least some of the first conductive contact structures436 a, the second conductive contact structures 436 b, and theadditional conductive routing structure 440.

As shown in FIG. 5, in contrast to the configurations and positions ofthe conductive routing structures 438 (FIG. 4), individual conductiverouting structures 538 may be coupled to and extend between firstconductive contact structures 436 a located on or over steps 424 ofdifferent stadium structures 422. For one or more (e.g., each) of thetiers 408 of the upper group 409 a defining the stadium structures 422 athrough 422 d and 422 f through 422 h, one or more conductive routingstructures 538 may individually electrically connect conductivestructures 428 of different stadium structures 422 (e.g., stadiumstructures 422 positioned in series with one another) of the tier 408 toform a continuous conductive path extending from the first end 432 ofthe conductive stack structure 426 to the second, opposing end 434 ofthe conductive stack structure 426. For example, for each of the tiers408 of the upper group 409 a defining the stadium structures 422 athrough 422 d and 422 f through 422 h, at least one conductive routingstructure 538 may extend from at least one first conductive contactstructure 436 a located on or over a step 424 of one or more of thestadium structures 422 a through 422 d (e.g., a step 424 of one or moreof the forward staircase structures 420 a, 420 c, 420 e, and 420 g,and/or a step 424 of one or more of the reverse staircase structures 420b, 420 d, 420 f, and 420 h) to at least one other first conductivecontact structure 436 a located on or over a step 424 of one or more ofthe stadium structures 422 f through 422 h (e.g., a step 424 of one ormore of the forward staircase structures 420 k, 420 m, and 420 o, and/ora step 424 of one or more of the reverse staircase structures 420 l, 420n, and 420 p). By way of non-limiting example, as shown in FIG. 5, foreach of the tiers 408 of the upper group 409 a defining the stadiumstructures 422 a through 422 d and 422 f through 422 h, a conductiverouting structure 438 may extend completely between a first conductivecontact structure 436 a located on or over a step 424 of the fourthstadium structure 422 d (e.g., on or over a step 424 of the fourthforward staircase structure 420 g, or on or over a step 424 of thefourth reverse staircase structure 420 h) and another first conductivecontact structure 436 a located on or over a step 424 of the eighthstadium structure 422 h (e.g., on or over a step 424 of the eighthforward staircase structure 420 o, or on or over a step 424 of theeighth reverse staircase structure 420 p).

In addition, as also shown in FIG. 5, optionally, at least one of thefirst conductive contact structures 436 a located on or over the steps424 of one or more of stadium structures 422 defined by the upper group409 a of the tiers 408 may be shared by at least one of the conductiverouting structures 538 and at least one of the additional conductiverouting structures 440. The additional conductive routing structure 440may be coupled to and extend between to the first conductive contactstructure 436 a and at least one of the string driver devices 442. Byway of non-limiting example, as depicted in FIG. 5, at least one of thefirst conductive contact structures 436 a located on or over a step 424of the fourth stadium structure 422 d may be shared by at least oneconductive routing structure 538 extending to at least one of the firstconductive contact structures 436 a located on or over a step 424 of theeighth stadium structure 422 h, and at least one additional conductiverouting structure 440 extending to at least one of the string driverdevices 442. Alternative to, or in combination with, sharing one or moreof the first conductive contact structures 436 a between the at leastone of the conductive routing structures 538 and at least one of theadditional conductive routing structures 440, one or more of the tiers408 of the upper group 409 a may be electrically connected to one ormore of the string driver devices 442 in the manner previously describedabove in relation to FIG. 4.

Similar to the configuration of the semiconductor device structure 400(FIG. 4), the configuration of the semiconductor device structure 500may permit individual switching devices (e.g., individual transistors)of the string driver devices 442 to drive voltages completely across(e.g., from the first end 432 to the second, opposing end 434) and/or inopposing directions across (e.g., toward the first end 432 and towardthe second, opposing end 434) individual tiers 408 of the conductivestack structure 426 electrically connected thereto.

Semiconductor devices (e.g., memory devices, such as 3D NAND Flashmemory device) including one or more of the semiconductor devicestructures 100, 200, 300, 400, 500 in accordance with embodiments of thedisclosure may be used in embodiments of electronic systems of thedisclosure. For example, FIG. 6 is a block diagram of an illustrativeelectronic system 600 according to embodiments of disclosure. Theelectronic system 600 may comprise, for example, a computer or computerhardware component, a server or other networking hardware component, acellular telephone, a digital camera, a personal digital assistant(PDA), portable media (e.g., music) player, a WiFi or cellular-enabledtablet such as, for example, an iPad® or SURFACE® tablet, an electronicbook, a navigation device, etc. The electronic system 600 includes atleast one memory device 602. The at least one memory device 602 mayinclude, for example, an embodiment of one or more of the semiconductordevice structures 100, 200, 300, 400, 500 shown in FIGS. 1A through 5(i.e., including FIGS. 1A through 1G, 2, 3A through 3F, 4, and 5). Theelectronic system 600 may further include at least one electronic signalprocessor device 604 (often referred to as a “microprocessor”). Theelectronic signal processor device 604 may, optionally, include asemiconductor device structure substantially similar to an embodiment ofone or more of the semiconductor device structures 100, 200, 300, 400,500 shown in FIGS. 1A through 5 (i.e., including FIGS. 1A through 1G, 2,3A through 3F, 4, and 5). The electronic system 600 may further includeone or more input devices 606 for inputting information into theelectronic system 600 by a user, such as, for example, a mouse or otherpointing device, a keyboard, a touchpad, a button, or a control panel.The electronic system 600 may further include one or more output devices608 for outputting information (e.g., visual or audio output) to a usersuch as, for example, a monitor, a display, a printer, an audio outputjack, a speaker, etc. In some embodiments, the input device 606 and theoutput device 608 may comprise a single touch screen device that can beused both to input information to the electronic system 600 and tooutput visual information to a user. The one or more input devices 606and output devices 608 may communicate electrically with at least one ofthe memory device 602 and the electronic signal processor device 604.

Thus, in accordance with embodiments of the disclosure, an electronicsystem comprises at least one semiconductor device structure comprisingstacked tiers each comprising at least one conductive structure and atleast one insulating structure longitudinally adjacent the at least oneconductive structure; at least one stadium structure comprising opposingstaircase structures having steps comprising lateral ends of the stackedtiers; at least one opening laterally adjacent the stadium structures,the at least one opening extending through the stacked tiers andcontinuously across an entire length of the at least one stadiumstructure; and at least one continuous conductive path at leastpartially formed by the at least one conductive structure of each of thestacked tiers and extending across an entire length of each of thestacked tiers.

The methods and structures of the disclosure may decrease the number ofswitching devices and interconnections required to drive voltagescompletely across and/or in different directions across a conductivestructure of a tier as compared to conventional methods and structuresassociated with various semiconductor devices (e.g., memory devices,such as 3D NAND Flash memory). The methods and structures of thedisclosure may permit a single switching device to drive an access line(e.g., word line) of a memory cell array from a more centralized (e.g.,middle, non-edge) location, which may reduce resistance x current (RC)delay by one-fourth (¼) as compared to conventional methods andstructures. The methods and structures of the disclosure may also reducecosts (e.g., manufacturing costs, material costs) and performance,scalability, efficiency, and simplicity as compared to conventionalstructures and methods.

While the disclosure is susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and have been described in detail herein.However, the disclosure is not limited to the particular formsdisclosed. Rather, the disclosure is to cover all modifications,equivalents, and alternatives falling within the scope of the followingappended claims and their legal equivalent

1. A method of forming a semiconductor device structure, comprising:forming a stack structure comprising stacked tiers each comprising aninsulating structure and an additional insulating structurelongitudinally adjacent the insulating structure; forming a maskingstructure over a portion of the stack structure; removing portions ofthe stacked tiers of the stack structure not covered by the maskingstructure to form at least one staircase structure having stepscomprising lateral ends of the stacked tiers; removing the maskingstructure after forming the at least one staircase structure; forming atleast one opening laterally inward of the at least one staircasestructure, the at least one opening extending through the stacked tiersand continuously across an entire length of the at least one staircasestructure; and replacing portions of the additional insulating structureof each of the stacked tiers with at least one conductive material toform at least one conductive structure in each of the stacked tiers, theat least one conductive structure extending continuously from at leastone of the steps of the at least one staircase structure and around theat least one opening to form at least one continuous conductive pathextending completely across each of the stacked tiers.
 2. The method ofclaim 1, further comprising: forming at least one contact structure onor over the at least one conductive structure of one or more of thestacked tiers at one or more of the steps of the at least one staircasestructure; and forming at least one routing structure to extend betweenthe at least one contact structure and at least one switching device. 3.The method of claim 1, wherein removing portions of the stacked tiers ofthe stack structure not covered by the masking structure to form atleast one staircase structure comprises selectively removing portions ofthe stacked tiers to form at least one stadium structure comprisingopposing staircase structures.
 4. The method of claim 3, wherein formingat least one opening comprises forming the at least opening tocontinuously laterally extend from a top of one of the opposingstaircase structures of the at least one stadium structure to a top ofanother of the opposing staircase structures of the at least one stadiumstructure.
 5. The method of claim 1, wherein removing portions of thestacked tiers of the stack structure not covered by the maskingstructure comprises removing portions of the stacked tiers adjacentopposing sides of the masking structure to form parallel staircasestructures each having steps comprising lateral ends of the stackedtiers.
 6. The method of claim 1, wherein replacing portions of theadditional insulating structure of each of the stacked tiers with atleast one conductive material comprises: removing the portions of theadditional insulating structure proximate lateral surfaces of thestacked tiers to form recessed regions laterally extending into each ofthe stacked tiers; and filling the recessed regions with the at leastone conductive material.
 7. A semiconductor device structure,comprising: stacked tiers each comprising conductive structures andinsulating structures longitudinally adjacent the conductive structures;stadium structures each comprising opposing staircase structures havingsteps comprising lateral ends of the stacked tiers; at least one openinglaterally intervening between at least two of the stadium structures,the at least one opening extending through the stacked tiers andcontinuously across entire lengths of the at least two stadiumstructures; conductive contact structures coupled to the conductivestructures of the stacked tiers at steps of the opposing staircasestructures of at least one of the stadium structures; and conductiverouting structures coupled to and extending completely between pairs ofthe conductive contact structures to form at least one continuousconductive path extending completely across each of the stacked tiers.8. The semiconductor device structure of claim 7, further comprisingadditional conductive routing structures coupled to at least some of theconductive contact structures and extending to at least one stringdriver device.
 9. The semiconductor device structure of claim 7, whereinthe stadium structures comprise: at least two stadium structuresextending parallel to one another; and at least two additional stadiumstructures extending parallel to one another and in series with the atleast two stadium structures.
 10. The semiconductor device structure ofclaim 9, wherein the at least one opening comprises: a first openinglaterally intervening between the at least two stadium structures andcontinuously extending across an entire length of each of the at leasttwo stadium structures; and a second opening laterally interveningbetween the at least two additional stadium structures and continuouslyextending across an entire length of each of the at least two additionalstadium structures.
 11. The semiconductor device structure of claim 9,wherein a first of the at least two additional stadium structurescomprises a first group of steps comprising lateral ends of a firstgroup of the stacked tiers, and wherein the second of the at least twoadditional stadium structures comprises a second group of stepscomprising lateral ends of a second, longitudinally lower group of thestacked tiers.
 12. The semiconductor device structure of claim 9,wherein at least one of the conductive routing structures is coupled toand extends completely between at least one conductive contact structureoverlying at least one step of one or more of the at least two stadiumstructures and at least one other conductive contact structure overlyingat least one step of one or more of the at least two additional stadiumstructures.
 13. A method of forming a semiconductor device structure,comprising: forming a stack structure comprising stacked tiers eachcomprising an insulating structure and an additional insulatingstructure longitudinally adjacent the insulating structure; removingportions of the stacked tiers of the stack structure to form at leastone stadium structure comprising opposing staircase structures; formingat least one opening extending through the stacked tiers andcontinuously across an entire length of the at least one stadiumstructure to form additional stadium structures each comprisingadditional opposing staircase structures having steps comprising lateralends of the stacked tiers; replacing portions of the additionalinsulating structure of each of the stacked tiers with at least oneconductive material to form conductive structures in each of the stackedtiers; coupling conductive contact structures to the conductivestructures of the stacked tiers at steps of the additional opposingstaircase structures of at least one of the additional stadiumstructures; and coupling conductive routing structures to and completelybetween pairs of the conductive contact structures to form at least onecontinuous conductive path extending completely across each of thestacked tiers.
 14. The method of claim 13, further comprising couplingadditional conductive routing structures to and completely between atleast one string driver device and at least some of the conductivecontact structures.
 15. The method of claim 13, wherein forming at leastone opening comprises forming at least two parallel openings extendingthrough the stacked tiers and continuously across the entire length ofthe at least one stadium structure.
 16. The method of claim 13, whereincoupling conductive routing structures to and completely between pairsof the conductive contact structures comprises coupling the conductiverouting structures to and completely between at least one pair of theconductive contact structures overlying opposing steps of the opposingstaircase structures of a single stadium structure.
 17. The method ofclaim 13, wherein coupling conductive routing structures to andcompletely between pairs of the conductive contact structures comprisescoupling the conductive routing structures to and completely between atleast one pair of the conductive contact structures overlying steps ofdifferent stadium structures.
 18. The semiconductor device structure ofclaim 7, wherein: four of the stadium structures extend parallel to oneanother in a first lateral direction; and three of the openings extendparallel to one another in the first lateral direction and separate thefour of the stadium structures from one another in a second lateraldirection perpendicular to the first lateral direction.
 19. Thesemiconductor device structure of claim 7, wherein the conductivecontact structures coupled to the conductive structures of the stackedtiers at steps of the opposing staircase structures of the at least oneof the stadium structures are substantially aligned with one anotheracross an entire length of the at least one of the stadium structures.20. The semiconductor device structure of claim 7, wherein at least oneof the stadium structures is free of any of the conductive contactstructures on the steps thereof.